a field guide to site identification and interpretation ... · sandra thomson, assistant ecologist,...

A Field Guide toSite Identification and

Interpretationfor the

Prince Rupert Forest Region

A. Banner, W. MacKenzie, S. Haeussler, S. Thomson, J. Pojar,and R. Trowbridge

AUTHORS AND AFFILIATIONS

Allen Banner, Regional Ecologist, Prince Rupert Forest Region, Ministry ofForests, Bag 5000, Smithers, B.C. V0J 2N0

Sybille Haeussler, Skeena Forestry Consultants, RR#2, S-81 C-2, Smithers,B.C. V0J 2N0

Will MacKenzie, Consulting Ecologist, Box 3652, Smithers, B.C. V0J 2N0

Jim Pojar, Forest Science Officer, Prince Rupert Forest Region, Ministry ofForests, Bag 5000, Smithers, B.C. V0J 2N0

Sandra Thomson, Assistant Ecologist, Prince Rupert Forest Region,Ministry of Forests, Bag 5000, Smithers, B.C. V0J 2N0

Rick Trowbridge, Soil Scientist, Prince Rupert Forest Region, Ministry ofForests, Bag 5000, Smithers, B.C. V0J 2N0

Canadian Cataloguing in Publication Data

Main entry under title:A Field guide to site identification and interpretation

for the Prince Rupert Forest Region

(Land management handbook, ISSN 0229-1622 ; no. 26)

Issued also in 2 part field handbook format. Includes bibliographical references: p. ISBN 0-7718-9396-5

1. Bioclimatology - British Columbia - Prince Rupert Region. 2. Biogeography - British Columbia - Prince Rupert Region. 3. Forest ecology - British Columbia - Prince Rupert Region. 4. Forest management - British Columbia - Prince Rupert Region. 5. Prince Rupert Forest Region (B.C.) I. Banner, Allen, 1954- . II. British Columbia. Ministry of Forests. III. Series.

QH541.5.F6F53 1993 581.5’2642’097111 C93-092435-5

© 1993 Province of British ColumbiaPublished by theResearch BranchMinistry of Forests31 Bastion SquareVictoria, B.C. V8W 3E7

Copies of this and other Ministry of Forests titles are available from Crown Publications Inc., 546 Yates Street, Victoria, B.C. V8W 1K8.

ii

Dr. Vladimir J. Krajina

(1905 – 1993)

PROFESSOR KRAJINA’S 40 years of teaching and research in ecology andconservation in British Columbia have inspired many of us to seek a betterunderstanding of the natural world. His life’s work provided the foundationfor ecologically based forest management in British Columbia.

iii

THIS FIELD GUIDE IS DEDICATED TO

DR. VLADIMIR J. KRAJINA

ACKNOWLEDGEMENTSThis field guide represents the synthesis of over 15 years of ecologicalsampling and analysis within the Prince Rupert Forest Region. Theclassification and interpretations presented in this guide have evolvedthrough the collective work of a great many individuals involved invarious phases of the ecosystem classification project since the mid1970s.

D.J. Wilford initially co-ordinated the project with J. Pojar in the mid tolate 1970s. The following individuals carried out field work andcontributed to our data base of over 2600 plots, on which the guide islargely based: R. Annas, C. Audet, K. Awmack, M. Blouw, W. Chapman,W.L. Chee, C. Clement, K.D. Coates, P. Comeau, R. Coupé, A. Deas, M.Geertsema, B.M. Geisler, E. Hamilton, S. Hardy, M. Hochachka, D.Holmes, A. Inselberg, D. Knowles, R. Laird, W. Lambkin, J. Lemieux, P.LePage, T. Lewis, S. Lindeburgh, A. Macadam, D.S. McLennan, K.McKeown, I.S. Moss, M. O’Neill, L. Ricciotti, B. Robinson, J. Schwab, K.Simonar, A. Smith, R. Smith, J.T. Standish, I. Teske, A. Waters, D.Wilford, T. Wood, K. Yearsley, and D. Yole. F. Boas, J. Godfrey, and T.Goward identified unknown bryophyte and lichen specimens.

Information from previous field guides and classification reports relevantto the Prince Rupert Forest Region has been updated, revised, andamalgamated into this new regional guide; the following authors of theseearlier reports are thus acknowledged: R.M. Annas, C. Clement, K.D.Coates, B.M. Geisler, D. Holmes, S. Houseknecht, A. Inselberg, K.Klinka, A. Kokoshke, T. Lewis, S. Lindeburgh, A. Macadam, D.S.McLennan, L. McCulloch, I.S. Moss, B. Robinson, K. Simonar, J.T.Standish, and D. Yole.

This field guide is based on a provincially correlated classification ofecological plot data made possible by the Correlation Program. D.Meidinger co-ordinated this correlation program and contributedsignificantly to the evolution of this guide. T. Fleming, S. Mah, C. Cadrin,A. Inselberg, and K. Yearsley provided valuable assistance with the dataanalysis for the correlation project. R. Coupé, C. Delong, R.N. Green, K.Klinka, and D. Meidinger were helpful in resolving correlation issueswith adjacent forest regions. T. Braumandl, M. Curran, R.N. Green, C.Delong, and D. Meidinger provided ideas and text for Chapters 1 to 3 ofthe guide as part of this correlation effort. In an effort to standardize sitedescription procedures provincially, many of the site description keysprovided in the appendices have been borrowed or modified from otherregional guides (Nelson, Kamloops, and Vancouver forest regions).

T. Ebata and S. Zeglan contributed the Forest Health section of the guideand B. Drinkwater contributed the Grass and Legume Seeding section.The Wildlife Interpretations chapter is based largely on informationinitially compiled by R. Lloyd, G. Radcliffe, and W. Klenner. D. Steventonprovided valuable input to the Wildlife chapter as well.

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Several individuals have contributed to the development of silviculturalinterpretations in the region. K.D. Coates, B.M. Geisler, R.N. Green, K.Klinka, A. Kokoshke, T. Lewis, I.S. Moss, L. McCulloch, as well asdistrict, regional, and industrial silviculture staff have all providedvaluable input throughout the ecological classification project.

A. Deas of Character Graphics produced most of the graphics and alsoprovided valuable advice and ideas on page layout and design. K.McKeown provided valuable assistance with graphics, word processing,editing, and paste-up.

Research Branch Productions Resources staff were very helpful in co-ordinating, editing, paste-up, and final publication and provided valuableadvice on layout and design; we thank P. Nystedt, H. Strongitharm, andD. Izard. G. Montgomery and S. Smith carried out the english editingand proofreading. The assistance of G. Britton with the final preparationof the camera-ready copy is very much appreciated.

Plant illustrations by the following artists have been utilized in theguide: F.L. Beebe, G. Bishop, T.C. Brayshaw, M. Bryant, P.Drukker-Brammall, P. Frank, G.F. Harcombe, A. Hassen, A. Havard,B.C. Newton, P. Nystedt, E.J. Steven, and R.A. With. We thank theRoyal British Columbia Museum and the British Columbia Ministry ofEnvironment, Lands and Parks for permission to use plant illustrationsfrom their publications.

We are grateful to the following individuals for their review comments onthe guide: P. Beaudry, G. Buhr, T. Braumandl, K.D. Coates, P. Comeau,C. Delong, M. Grainger, R.N. Green, P. Hanna, G. Krumlick, T. Lea, P.LePage, G. Lloyd, D.S. McLennan, A. MacKinnon, S. Mah, D. Meidinger,A. Nicholson, A. Inselberg, D. Steventon, and B. Wilson.

Financial support for the preparation and publication of this guide wasprovided by the Correlation Project (Research and Silviculture Branches)and by the Silviculture Section, Prince Rupert Forest Region. We thankD. Meidinger, G. Lloyd, N. Endacott, and K. Geertsema for providing andadministering these funds.

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TABLE OF CONTENTS

AUTHORS AND AFFILIATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iiDEDICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iiiACKNOWLEDGEMENTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv

1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1•11.1 Objectives and Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1•11.2 Other Sources of Information . . . . . . . . . . . . . . . . . . . . . . . . . . . 1•11.3 Guide Content and Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . 1•31.4 Format of the Guide. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1•31.5 Training Courses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1•4

2 BIOGEOCLIMATIC ECOSYSTEM CLASSIFICATION . . . . . . . . . . . 2•1

2.1 The Classification System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2•12.2 Climate Classification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2•1

2.2.1 Naming of biogeoclimatic units . . . . . . . . . . . . . . . . . . . . . 2•32.3 Site Classification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2•4

2.3.1 Naming and numbering of site units. . . . . . . . . . . . . . . . . 2•52.4 Seral Classification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2•52.5 Ecoregion Classification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2•6

3 PROCEDURES FOR SITE DESCRIPTION,IDENTIFICATION, AND MAPPING . . . . . . . . . . . . . . . . . . . . . . . . . . 3•l

3.1 Identifying Biogeoclimatic Units . . . . . . . . . . . . . . . . . . . . . . . . . 3•13.2 Describing and Identifying Site Units . . . . . . . . . . . . . . . . . . . . . 3•2

3.2.1 Describing site units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3•23.2.2 Identifying site units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3•43.2.3 Identifying seral ecosystems . . . . . . . . . . . . . . . . . . . . . . 3•10

3.3 Mapping Site Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3•10

vi

4 BIOGEOCLIMATIC UNITS OF THE PRINCE RUPERTFOREST REGION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4•1

4.1 Physiography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4•14.2 Biogeoclimatic Units of the South Half of the

Prince Rupert Forest Region . . . . . . . . . . . . . . . . . . . . . . . . . . . 4•54.2.1 AT Alpine Tundra Zone . . . . . . . . . . . . . . . . . . . . . . . . . . 4•134.2.2 CWH Coastal Western Hemlock Zone . . . . . . . . . . . . . . . 4•174.2.3 ESSF Engelmann Spruce – Subalpine Fir Zone . . . . . . . 4•274.2.4 ICH Interior Cedar – Hemlock Zone . . . . . . . . . . . . . . . . 4•354.2.5 MH Mountain Hemlock Zone . . . . . . . . . . . . . . . . . . . . . 4•434.2.6 SBPS Sub-Boreal Pine – Spruce Zone . . . . . . . . . . . . . . . 4•474.2.7 SBS Sub-Boreal Spruce Zone. . . . . . . . . . . . . . . . . . . . . . 4•55

4.3 Biogeoclimatic Units of the North Half of thePrince Rupert Forest Region . . . . . . . . . . . . . . . . . . . . . . . . . . 4•594.3.1 AT Alpine Tundra Zone . . . . . . . . . . . . . . . . . . . . . . . . . . 4•674.3.2 BWBS Boreal White and Black Spruce Zone . . . . . . . . . 4•694.3.3 CWH Coastal Western Hemlock Zone . . . . . . . . . . . . . . . 4•774.3.4 ESSF Engelmann Spruce – Subalpine Fir Zone . . . . . . . 4•814.3.5 ICH Interior Cedar – Hemlock Zone . . . . . . . . . . . . . . . . 4•854.3.6 MH Mountain Hemlock Zone . . . . . . . . . . . . . . . . . . . . . 4•874.3.7 SBS Sub-Boreal Spruce Zone. . . . . . . . . . . . . . . . . . . . . . 4•894.3.8 SWB Spruce – Willow – Birch Zone . . . . . . . . . . . . . . . . 4•91

5 SITE UNITS OF THE PRINCE RUPERT FOREST REGION . . . . . . 5•1

5.1 Boreal White and Black Spruce Zone. . . . . . . . . . . . . . . . . . . . . 5•3BWBSdk1 Dry Cool Subzone – Stikine Variant. . . . . . . . . . . . . 5•4BWBSdk2 Dry Cool Subzone – Liard Variant . . . . . . . . . . . . . 5•12

5.2 Coastal Western Hemlock Zone . . . . . . . . . . . . . . . . . . . . . . . . 5•21CWHvh2 Very Wet Hypermaritime Subzone –

Central Variant. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5•22CWHvm1 Very Wet Maritime Subzone –

Submontane variant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5•40CWHvm2 Very Wet Maritime Subzone –

Montane Variant. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5•48CWHwm Wet Maritime Subzone . . . . . . . . . . . . . . . . . . . . . . . 5•56CWHwsl Wet Submaritime Subzone –

Submontane Variant. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5•64

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CWHws2 Wet Submaritime Subzone –Montane Variant. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5•72

5.3 Engelmann Spruce – Subalpine Fir Zone . . . . . . . . . . . . . . . . 5•81ESSFmc Moist Cold Subzone . . . . . . . . . . . . . . . . . . . . . . . . . . 5•82ESSFmk Moist Cool Subzone . . . . . . . . . . . . . . . . . . . . . . . . . . 5•90ESSFwv Wet Very Cold Subzone . . . . . . . . . . . . . . . . . . . . . . . 5•98

5.4 Interior Cedar – Hemlock Zone . . . . . . . . . . . . . . . . . . . . . . . 5•107ICHmc1 Moist Cold Subzone – Nass Variant . . . . . . . . . . . . 5•108ICHmc1a Moist Cold Subzone – Nass Variant –

Amabilis Fir Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5•116ICHmc2 Moist Cold Subzone – Hazelton Variant, . . . . . . . . . 5•124ICHvc Very Wet Cold Subzone. . . . . . . . . . . . . . . . . . . . . . . . 5•136ICHwc Wet Cold Subzone. . . . . . . . . . . . . . . . . . . . . . . . . . . . 5•144

5.5 Mountain Hemlock Zone . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5•153MHmm1 Moist Maritime Subzone –

Windward Variant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5•154MHmm2 Moist Maritime Subzone –

Leeward Variant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5•162MHwh1 Wet Hypermaritime Subzone –

Windward Variant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5•1705.6 Sub-Boreal Pine – Spruce Zone . . . . . . . . . . . . . . . . . . . . . . . 5•179

SBPSmc Moist Cold Subzone . . . . . . . . . . . . . . . . . . . . . . . . . 5•1805.7 Sub-Boreal Spruce Zone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5•189

SBSdk Dry Cool Subzone . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5•190SBSmc2 Moist Cold Subzone – Babine Variant . . . . . . . . . . . 5•198

6 WILDLIFE HABITAT INTERPRETATIONS. . . . . . . . . . . . . . . . . . . . 6•1

6.1 Regional Wildlife Diversity . . . . . . . . . . . . . . . . . . . . . . . . . 6•26.2 Overview of Wildlife Species and Habitats for the

Biogeoclimatic Zones and Subzones . . . . . . . . . . . . . . . . . . 6•36.2.1 Alpine Tundra Zone . . . . . . . . . . . . . . . . . . . . . . . . . 6•36.2.2 Boreal White and Black Spruce Zone . . . . . . . . . . . . 6•46.2.3 Coastal Western Hemlock Zone . . . . . . . . . . . . . . . . . 6•56.2.4 Engelmann Spruce – Subalpine Fir

and Mountain Hemlock Zones . . . . . . . . . . . . . . . . . . 6•66.2.5 Interior Cedar – Hemlock Zone . . . . . . . . . . . . . . . . . 6•86.2.6 Sub-Boreal Pine – Spruce and

Sub-Boreal Spruce Zones . . . . . . . . . . . . . . . . . . . . . . 6•96.2.7 Spruce – Willow – Birch Zone . . . . . . . . . . . . . . . . . 6•10

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6.3 Habitats, Habitat Components, and Species ofManagement Concern . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6•106.3.1 Key habitats (landscape-level components) . . . . . . . 6•116.3.2 Important habitat components

(stand-level components) . . . . . . . . . . . . . . . . . . . . . 6•146.3.3 Species groups and selected species of

management concern . . . . . . . . . . . . . . . . . . . . . . . . 6•166.4 Wildlife Habitat Considerations in Timber Harvesting

and Silvicultural Planning . . . . . . . . . . . . . . . . . . . . . . . . 6•166.4.1 General guidelines for maintaining

wildlife habitat values . . . . . . . . . . . . . . . . . . . . . . . 6•196.4.2 Harvesting considerations,. . . . . . . . . . . . . . . . . . . . 6•216.4.3 Stand management considerations . . . . . . . . . . . . . 6•24

6.5 Summary of Wildlife Habitat Considerationsin Pre-Harvest Silvicultural Prescriptions . . . . . . . . . . . . 6•25

7 SILVICULTURAL INTERPRETATIONS. . . . . . . . . . . . . . . . . . . . . . . 7•17.1 Forest Productivity and Regeneration:

Ecological Principles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7•27.1.1 Climate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7•27.1.2 Soil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7•57.1.3 Vegetation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7•10

7.2 Interpretations Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . 7•167.2.1 Site series . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7•167.2.2 Productivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7•167.2.3 Limiting factors for productivity

and regeneration . . . . . . . . . . . . . . . . . . . . . . . . . . . 7•177.2.4 Vegetation potential and complexes. . . . . . . . . . . . . 7•187.2.5 Tree species selection guidelines.. . . . . . . . . . . . . . . 7•227.2.6 Reforestation considerations . . . . . . . . . . . . . . . . . . 7•26

7.3 Forest Health . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7•747.4 Grass and Legume Seeding . . . . . . . . . . . . . . . . . . . . . . . . 7•80

7.4.1 Developing a seeding prescription . . . . . . . . . . . . . . 7•81

8 LITERATURE CITED. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8•1

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APPENDICES

1 Ecosystem classification, interpretive, and plantguide references relevant to the PRFR. . . . . . . . . . . . . . . . . . . . . . . A•3

2 Correlation between old and new biogeoclimaticand site units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A•12

3 Tree species codes and symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . A•174 Ecoregion classification in the PRFR . . . . . . . . . . . . . . . . . . . . . . . A•195 Sample ecological classification reconnaissance plot form . . . . . . . A•246 Relative and actual soil moisture relationships . . . . . . . . . . . . . . . A•267 Soil moisture regime identification key . . . . . . . . . . . . . . . . . . . . . A•288 Soil nutrient regime identification table. . . . . . . . . . . . . . . . . . . . . A•309 Landform identification key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A•3210 Key to common rock types of the PRFR . . . . . . . . . . . . . . . . . . . . . A•3411 Soil texturing key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A•3512 A soil classification key, to the great group level . . . . . . . . . . . . . . A•4013 Humus forms key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A•4214 Common plants of the Prince Rupert Forest Region . . . . . . . . . . . A•4415 Comparison charts for visual estimation of foliage cover . . . . . . . . A•5016 Mapping procedures for treatment unit maps . . . . . . . . . . . . . . . . A•5117 Free growing stocking standards and guidelines

for the PRFR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A•5418 Glossary of common and scientific names of common

forest pests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A•61

TABLES

2.1 Connotative codes used for subzone names in the PRFR . . . . . . . . . 2•33.1 Abbreviations used to describe parent materials . . . . . . . . . . . . . . . 3•83.2 Abbreviations used to describe soil particle size . . . . . . . . . . . . . . . . 3•83.3 Abbreviations for soil classification used in this field guide . . . . . . . 3•94.1 Physiographic subdivisions of the PRFR. . . . . . . . . . . . . . . . . . . . . . 4•34.2 Environmental characteristics of all zones in

the PRFR, south half . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4•6

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4.3 Climatic characteristics of all forested zones inthe PRFR, south half . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4•8

4.4 Environmental characteristics of CWH subzonesand variants in the PRFR, south half . . . . . . . . . . . . . . . . . . . . . . . 4•20

4.5 Environmental characteristics of ESSF and MHsubzones and variants in the PRFR, south half . . . . . . . . . . . . . . . 4•30

4.6 Environmental characteristics of ICH subzones, variants,and phases in the PRFR, south and north halves. . . . . . . . . . . . . . 4•38

4.7 Environmental characteristics of SBPS and SBSsubzones and variants in the PRFR, south half . . . . . . . . . . . . . . . 4•50

4.8 Environmental characteristics of all forested zonesin the PRFR, north half . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4•60

4.9 Climatic characteristics of all forested zones in thePRFR, north half . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4•62

4.10 Environmental characteristics of BWBS subzones andvariants in the PRFR, north half. . . . . . . . . . . . . . . . . . . . . . . . . . . 4•72

6.1 Selected species management groups . . . . . . . . . . . . . . . . . . . . . . . 6•126.2 Habitat features of selected species of

management concern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6•176.3 Potential impacts of broad management activities on

important stand structure attributes . . . . . . . . . . . . . . . . . . . . . . . 6•206.4 Preliminary seral stage objectives by biogeoclimatic zone . . . . . . . 6•206.5 Preliminary minimum structural objectives to be

maintained for mature second-growth stands on zonal sites . . . . . 6•217.1 Vegetation potential classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7•187.2 Major complexes of competing vegetation in the PRFR . . . . . . . . . 7•197.3 Slashburning severity levels and approximate

fuel consumption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7•277.4 Major pests of spruce in four biogeoclimatic zones

of the PRFR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7•767.5 Major pests of lodgepole pine in four biogeoclimatic

zones of the PRFR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7•777.6 Major pests of amabilis fir and subalpine fir in four

biogeoclimatic zones of the PRFR . . . . . . . . . . . . . . . . . . . . . . . . . . 7•787.7 Major pests of western hemlock in two biogeoclimatic

zones of the PRFR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7•79

xi

7.8 Major pests of western redcedar and yellow-cedar intwo biogeoclimatic zones of the PRFR . . . . . . . . . . . . . . . . . . . . . . 7•79

7.9 Major pests of trembling aspen and black cottonwoodin three biogeoclimatic zones of the PRFR . . . . . . . . . . . . . . . . . . 7•80

7.10 Suggested seed mixes for different uses and siteconditions in the PRFR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7•83

7.11 Attributes and tolerances of recommended grassand legume species for use in seed mixes in the PRFR. . . . . . . . . 7•84

FIGURES

1.1 Location of the Prince Rupert Forest Region andForest Districts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1•2

2.1 The hierarchical structure of the climate and siteclassification in the BEC system . . . . . . . . . . . . . . . . . . . . . . . . . . . 2•2

2.2 An illustration of the structural and developmentalstages used in seral classification . . . . . . . . . . . . . . . . . . . . . . . . . . 2•5

3.1 A flowchart outlining the procedure for identifying site units . . . . 3•33.2 An example of an edatopic grid . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3•53.3 An example of a vegetation table. . . . . . . . . . . . . . . . . . . . . . . . . . . 3•63.4 Mesoslope position diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3•73.5 An example of a landscape profile diagram. . . . . . . . . . . . . . . . . . . 3•93.6 Flowchart outlining the ecosystem mapping process . . . . . . . . . . 3•114.1 Map showing the division of the PRFR into north

and south halves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4•24.2 Vegetation table for all forested zones in the

PRFR, south half . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4•104.3 Distribution of the AT zone in the PRFR . . . . . . . . . . . . . . . . . . . 4•144.4 Distribution of CWH subzones in the PRFR; south half . . . . . . . . 4•184.5 Vegetation table for CWH subzones and variants in

the PRFR, south half . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4•224.6 Distribution of forested ESSF subzones and variants

in the PRFR, south half . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4•284.7 Vegetation table for ESSF and MH subzones and variants

in the PRFR, south half . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4•32

xii

4.8 Distribution of ICH subzones and variants in thePRFR, south half . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4•36

4.9 Vegetation table for ICH subzones and variantsin the PRFR, south and north halves . . . . . . . . . . . . . . . . . . . . . . 4•40

4.10 Distribution of MH variants in the PRFR, south half . . . . . . . . . . 4•444.11 Distribution of SBPS and SBS subzones and variants

in the PRFR, south half . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4•484.12 Vegetation table for SBPS and SBS subzones and

variants in the PRFR, south half. . . . . . . . . . . . . . . . . . . . . . . . . . 4•524.13 Vegetation table for all forested zones in the

PRFR, north half . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4•644.14 Distribution of BWBS subzones and variants in the

PRFR, north half . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4•704.15 Vegetation table for BWBS subzones and variants

in the PRFR, north half . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4•744.16 Distribution of CWH, ICH, and SBS zones in the

PRFR, north half . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4•784.17 Distribution of ESSF, MH, and SWB zones in the

PRFR, north half . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4•827.1 Microtopographic variation in surface soil characteristics

and soil climate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7•77.2 Relative ranking of ecological tolerances and nutritional

requirements for major tree species in the PRFR . . . . . . . . . . . . . 7•24

xiii

5.5 MOUNTAIN HEMLOCK ZONE

The Mountain Hemlock zone (MH) in the PRFR has been subdivided into thefollowing forested biogeoclimatic units:

MHmm - Moist Maritime (Forested) subzone MHmm1 - Windward variant MHmm2 - Leeward variant

MHwh - Wet Hypermaritime (Forested) subzone MHwh1 - Windward variant

Above each of the two forested subzones is a corresponding parkland subzoneoccupying the transition from treeline to true alpine tundra (AT zone). Only theforested subzones are described in this guide.

Description and differentiation of biogeoclimatic units:PRFR - South: page 4 • 43PRFR - North: page 4 • 87

Interpretations:

Wildlife: page 6 • 6Silviculture: page 7 • 62

Application of site classification in the MH zone:

The severe climate (heavy snow, short growing seasons, severe exposure towind, cold, and wet soils) has a dominant and overriding effect on vegetationdevelopment and forest productivity in this subalpine zone. Although we havetentatively defined several site series to describe the edaphic variabilityoccurring within our forested MH subzones, this ecological variability isgenerally not reflected in the vegetation and forest productivity to the extentseen in most other zones (including the interior subalpine ESSF). This is largelydue to the exposed conditions and cold, moist to wet soils, with relatively thick,compact (Mor) humus forms that prevail on most sites in the MH zone. Thus,many of the forested plant associations over a range of edatopes share a similarassemblage of species (albeit in varying amounts), and most sites, regardless ofedaphic characteristics, exhibit low to poor forest productivity.

The above factors, combined with our very limited sampling of the MH zone,makes site description and classification relatively difficult. To date, there hasbeen little or no forest harvesting in the MH zone of the PRFR and most of this zone is inaccessible because of its steep terrain. Much more ecologicalinformation is needed from those areas that are accessible before anydevelopment in this sensitive zone occurs.

Classification and description of site series presented here should be considered a first approximation pending further field work.

MH

5 • 153

MHmm 1Moist Maritime Subzone

Windward Variant

Adjacent biogeoclimatic units: CWHvm occurs at lower elevations in thesouth and CWHwm at lower elevations in the north; MHmm2 at similarelevations inland; MHwh1 at similar elevations towards the coast; MHmm1parkland at higher elevations.

Elevation range: 800 - 1200 m.

Description and comparison of site series:

See notes on application of site classification in the MH zone, page 5 • 153.

Zonal site series:

01 HmBa - Blueberry is common throughout the subzone. Zonal forests occurmostly on colluvial deposits and on localized morainal or organic (LFH) veneersover bedrock from upper to mid slopes. Overall, the steep MH landscape hasvery little glacial till. Forests are typically closed Hm/Ba stands with acontinuous blueberry understory. The herb layer is usually sparse and of poorproductivity, and is represented by five-leaved bramble and a few scatteredsubalpine indicators such as pink mountain-heather. A continuous moss layer iscomposed mainly of pipecleaner, heron’s-bill, and lanky mosses. In the MHzone, forest productivity on most sites is limited by the severe climate. However,the best stands generally occur on steep, colluvial slopes with free drainage.

Drier sites: One drier forested site series is recognized.

02 HmBa - Mountain-heather occurs on the driest forested sites, mostly onexposed upper slopes and ridge crests with rapid drainage and lower snowloading. Severe exposure to wind is probably the most important controllingfactor for this site series. Forests are scrubby and consist of open Hm/Ba standswith a thick shrub layer. Blueberry, copperbush, huckleberry, false azalea, andconifer regeneration are all abundant. Dwarf woody shrubs, such as white andpink mountain-heather, are common.

Moist to wet sites: Seven wetter forested site series are recognized.

03 BaHm - Oakfern occurs on rich colluvial or morainal parent materials,often on moderate slopes that receive seasonal seepage at depth. This is themost productive unit in the variant, supporting moderately sized Ba, Hm, Yc,and sometimes Hw. Devil’s club is common in this unit, as is salmonberry andSitka alder. Herbs that reflect rich site conditions, such as twistedstalk, ladyfern, foamflower, and oak fern, are common. Feathermosses and leafy mossesco-dominate. This site series is closely aligned to the 05 site series and floristicdifferences are subtle. However, the 05 site series has wetter conditions,reflected in its Gleysolic or gleyed soils and poorer stand productivity.

04 HmBa - Bramble occurs on steep seepage slopes that have a high content ofcoarse fragments. Forests are similar in composition to 01 forests, but,generally, shrub and herb layers are better developed. Soils are also similar, butinfluenced more by subsurface seepage than are those on 01 sites.

Site Units

5 • 154

05 BaHm - Twistedstalk is fairly common in the variant on lower slopeswhere abundant seepage leads to wet conditions. The nutrient regime is rich,but excess moisture limits forest productivity. Vegetation is similar to that inthe 03 site series, with rich-site indicators such as devil’s club, twistedstalk, oakfern, and foamflower occurring. Gleysolic or heavily mottled soils and poorerforest productivity distinguish 05 from 03.

06 HmYc - Deer-cabbage forests occur on flat ridge crests, gradual slopes, anddepressions where melting snowpacks keep soils saturated and cold for most ofthe growing season. Forests are very scrubby Hm/Yc/Ba mixtures. Thick shrublayers of copperbush, blueberry, and false azalea are typical. Five-leavedbramble and deer-cabbage are usually abundant in the herb layer.

07 YcHm - Hellebore occurs on moderately steep to steep, wet, seepage slopes.Gleysols derived from colluvium (or morainal till) are typical. Stands arescrubby and open with a diverse and lush herb layer dominated by whitemarsh-marigold, lady fern, foamflower, Indian hellebore, twistedstalk, leafymosses, and sphagnum. The 07 is distinguished from the drier 05 site series bya lower shrub and tree cover, the presence of white marsh-marigold, and theobvious dominance of leafy mosses and sphagnum. This site series grades intoother site series of adjacent edatopes (05, 06, 09) and distinguishing the 07 fromthese is often difficult.

08 HmYc - Sphagnum is restricted in occurrence. These wet bog forests arefound on level ridge crests or depressions, often in complex with non-forestedwetlands (31). Soils are Mesisols. These very scrubby, open Hm/Yc forests arecharacterized by dense understories of blueberry, copperbush, false azalea, andconifer regeneration. Deer-cabbage, white marsh-marigold, five-leaved bramble,and bunchberry are the common herbs for this unit. The moss layer is a mix oflanky and step mosses and sphagnum. The 08 typically intergrades into 06.

09 YcHm - Skunk cabbage has a diverse canopy of Hm, Yc, Ba, and Hw;productivity is low because of saturated, cold, poorly aerated soil conditions.Sites are usually localized on lower wet seepage slopes and depressions thathave mineral seepage influence. Understory vegetation is lush and very diverse.Skunk cabbage, Indian hellebore, and other rich-site indicators such as oak fernand lady fern are typical. The 09 is often in complex with 05 and 06 forests.

Non-forested site units: Two non-forested site units are described for the MHzone: Non-forested wetland (31) and Avalanche track (51).

The steep rugged terrain limits wetland formation over most of the subzone, but Non-forested wetlands are common in localized depressional areas andon some gentle to moderate slopes where high and stagnant water tables, latesnowmelt, and cold, peaty soils limit tree establishment and growth.Characteristic species include copperbush, mountain-heather, deer-cabbage,marsh-marigold, sedges, clubrush, and sphagnum.

In the MHmm subzone, deep snowpacks and steep terrain lead to the formationof large areas of Avalanche track ecosystems. Periodic or annual snowslidesremove trees, keeping these sites in a young shrub seral stage. As a result ofcolluvial mixing and constant seepage, avalanche tracks are rich and supportlush shrub and herb communities. Sitka alder, willows, salmonberry, lady fern,and Sitka valerian are typical avalanche track species.

MHmm1

5 • 155

MH

mm

1 L

and

scap

e P

rofi

lea

Site Units

5 • 156

aT

ree

sym

bols

are

def

ined

in

App

endi

x 3.

Sit

e S

erie

s

01 H

mB

a -

Blu

eber

ry02

Hm

Ba

-M

oun

tain

-hea

ther

03 B

aHm

-O

ak f

ern

04 H

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Bra

mbl

e05

BaH

m -

Tw

iste

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lk51

Ava

lan

che

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eer-

cabb

age

07 Y

cHm

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elle

bore

08 H

mY

c -

Sph

agn

um

09 Y

cHm

-S

kun

k ca

bbag

e31

Non

-for

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and

actu

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MR

are

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in

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endi

ces

6 an

d 7.

MHmm1

5 • 157

MH

mm

1 E

dat

opic

Gri

d

MHmm1 Site Series Flowchart

Site Units

5 • 158

NON-FORESTED

WETLANDSTree cover < 10%.

FRESH TO

MOIST FORESTSMoisture regime 4-5.

Sites not clearly wet

or dry.

AVALANCHE

TRACKSNo trees.

VERY MOIST TO

WET FORESTSMoisture regime 6-7.

Seepage slopes and

depressions.

DRY TO FRESH

FORESTSMoisture regime 0-3.

Ericaceous shrubs, deer-cabbage, sedges, and 31sphagnum common. Non-forested

wetlands

Colluvial slopes on steep terrain. Sitka alder, 51willow, and salmonberry thickets. Ferns, Avalanche tracktwistedstalk, and Sitka valerian common.

Exposed rocky knolls. Copperbush, moun- 02 HmBa -tain-heather, and blueberries abundant. Mountain-

heather

Upper and mid slopes. Copperbush, mountain- 01heathers, and rich-site indicators uncommon. HmBa - Blueberry

Mid to lower slopes. Copperbush and moun- 03tain-heathers absent. Ferns, twistedstalk, and BaHm - Oak fernfoamflower (rich-site indicators) abundant.

Very wet sites. Skunk cabbage abundant; 09 YcHm - Skunkrich-site indicators common. cabbage

Very wet sites. Skunk cabbage scattered; few 08rich-site indicators; copperbush and sphagnum HmYc -abundant. Sphagnum

Wet sites. Skunk cabbage scattered; marsh- 07marigold and rich-site indicators abundant. YcHm - Hellebore

Wet sites. No skunk cabbage and scattered 06sphagnum; few rich-site indicators; copperbush HmYc - Deer-and deer fern abundant. cabbage

Poor to medium productivity. Soils gleyed. 05Rich-site indicators (devil’s club, twistedstalk, BaHm -lady fern, foamflower) scattered to common. Twistedstalk

Moderately productive forests. Abundant 03rich-site indicators (devil’s club, Sitka alder, BaHm - Oak fernsalmonberry, oak fern, lady fern).

Poor-productivity Hm - blueberry forests. Few 04rich-site indicators. Herb layer moderately HmBa - Bramblewell developed.

Poor to moderately productive Hm - blueberry 01forests. Few rich-site indicators; herb layer HmBa - Blueberrygreatly reduced.

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MHmm1

5 • 159

MH

mm

1 V

eget

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n T

able

a

MHmm1 Environment Table

SoilSite moisture/ Slope %series Phase nutrients Slope position range Parent materiala

01 2-4/A-C upper - mid 10 - 75 C, Ov/C, (M)

02b 0-1/A-C crest 0 - 60 Ov/R, (Mv/R)

03 2-4/D-E mid - toe 20 - 65 C, (Ov/R), (M)

04 5/A-C mid (upper) 3 - 85 C, Cv/R, (M)

05 5/D-E mid - toe 9 - 85 C, (M)

06b 6/A-C crest - upper 10 - 35 C, (M)

07b 6/D-E upper - lower 30 - 60 C, Ov/R, M

08b 7/A-B lower 10 - 30 O

09b 7/C-E lower 3 - 50 C, M

31 7+/A-E upper - lower, 5 - 60 Odepressions

51 5-6/D-E upper - lower 5 - 85 C

a Codes are described in Section 3.2.2, page 3 • 8.

b Limited data; unit described from fewer than three plots.

Site Units

5 • 160

Humus formSoil Soil Depth (cm)particle sizea classificationa min-mean-max Important site features

Ls, KL, (L) HFP, FHP, FO Mors Most common site series on mid to5 - 21 - 48 upper slopes.

Ss, KL(s) HP, FO Mors Extreme exposure to wind.10 - 21 - 37

Ls, KL, (L) HFP, (FO) Mors Freely drained, relatively productive3 - 18 - 42 sites.

FLs, Ss FHP, HFP Mors Similar to 01 but greater seepage2 - 18 - 40 influence.

Ls G, HFP, R Mors Seepage sites. Gleyed soils limit(gleyed) 2 - 21 - 68 productivity.

L HFP; gleyed Mors Deep, long-lasting snowpacks. Low-10 - 15 - 25 productivity forests.

FL, L G Mors Rooting and productivity restricted in10 - 20 - 30 wet, cold soils.

-- M peaty “O” horizons Very wet, poor bog forests; limited>60 cm extent.

S, KL G Mors, Moders Very wet, but mineral-rich swamp5 - 31 - 65 forests. Uncommon.

-- F peaty “O” horizons Non-forested wetlands. Soils too wet>75 cm and cold for tree growth.

S, L R, DYB Moders Rich site conditions from colluvial1 - 6 - 0 mixing and deciduous litterfall.

MHmm1

5 • 161

MHmm2Moist Maritime Subzone

Leeward Variant

Adjacent biogeoclimatic units: CWHws2 at lower elevations; ESSFwv atsimilar elevations inland in the north; ESSFmk at similar elevations inland inthe south; MHmm1 at similar elevations towards the coast; MHmm2 parklandand AT at higher elevations.



(See notes on application of site classification in the MH zone, page 5 • 153.)

Zonal site series:

01 HmBa - Blueberry is common throughout the subzone. Zonal forests occurmostly on colluvial deposits and on localized morainal and organic veneers overbedrock, from upper to mid slopes. Overall, the steep MH landscape has verylittle glacial till. Forests are typically closed Hm/Ba stands of poor productivitywith a continuous blueberry/huckleberry understory. In contrast to MHmm1,these less maritime MHmm2 mesic sites often have a subalpine fir component,little or no yellow-cedar, and an abundance of black huckleberry. The herb layeris usually sparse and represented by five-leaved bramble and perhaps a fewscattered subalpine mountain-heather species. A continuous moss layer iscomposed mainly of pipecleaner and heron’s-bill moss, and red-stemmedfeathermoss. In the MH zone, forest productivity on most sites is limited by thesevere climate. However, the best stands generally occur on steep, colluvialslopes with free drainage.

Drier sites: One drier forested site series is recognized.

02 HmBa - Mountain-heather occurs on xeric and subxeric sites, mostly onexposed upper slopes and ridge crests with rapid drainage and lower snowloading. Forests are scrubby and open Hm, Ba, (Bl), and (Hw) stands with athick shrub layer; Yc may occur in the westernmost portions of the variant.Blueberry, copperbush, huckleberry, false azalea, and conifer regeneration areall abundant. Herbs are scattered pink mountain-heather and five-leavedbramble. Severe exposure to wind is an important controlling factor for this siteseries.

Fresh to wet sites: Seven wetter forested site series are recognized.

03 BaHm - Oak fern occurs on rich colluvial (or morainal) parent materials,often on moderate slopes that receive some seasonal seepage at depth. This isthe most productive unit in the variant supporting moderately sized Ba, Hm,and Bl. Scattered devil’s club and Sitka alder occur in this unit. Herbs thatreflect rich site conditions, such as twistedstalk, lady fern, foamflower, and oakfern are common. The moss layer is diverse but only moderately developed;pipecleaner moss, red-stemmed feathermoss, leafy mosses, and leafy liverwortsco-dominate with lanky and step mosses. As in the MHmm1, this site series isclosely aligned to the 05, and its floristic composition is very similar. Site

Site Units

5 • 162

conditions are most useful in distinguishing the 03 from the 05; the 05 siteseries has wetter conditions reflected in gleyed soils, and poorer standproductivity.

04 HmBa - Bramble occurs on steep seepage slopes that have a high content ofcoarse fragments. Forests are similar in composition to zonal sites but,generally, shrub and herb layers are better developed. Soils are also similar butare influenced more by subsurface seepage. As in the 01, Bl may occur in thisunit.

05 BaHm - Twistedstalk is common in the variant on lower slopes withabundant seepage. Conditions are rich, but productivity is limited by excessmoisture. Vegetation is similar to that in the 03 site series, with rich-siteindicators such as devil’s club, rosy twistedstalk, oak fern, and foamflower oftenbeing found. Gleysolic or heavily mottled soils and poorer forest productivitydistinguish the 05 from the 03.

06 HmYc - Deer-cabbage scrub forests occur on flat ridge crests and gradualslopes and depressions where melting snowpacks keep soils saturated and coldfor most of the growing season. Forests are very scrubby and dominated by Hmwith scattered Ba and Yc. Thick shrub layers of blueberries, copperbush, andfalse azalea are common. Deer-cabbage is abundant and a key indicator speciesin these wet scrub forests.

07 YcHm - Hellebore occurs on moderately steep to steep, wet seepage slopes.Gleysols derived from colluvium (or morainal till) are typical. The scrubby, openforests are Hm dominated. Herbs such as Indian hellebore, deer-cabbage, androsy twistedstalk dominate. The 07 grades into the 05, 06, and 09 site series.Distinguishing between these related site series may be difficult.

08 HmYc - Sphagnum is rare in the variant. These wet bog forests are foundon level ridge crests or depressions, often complexed with poorer Non-forestedwetlands (31). Soils are Mesisols. Very scrubby open Hm forests arecharacterized by dense understories of blueberry, copperbush, false azalea, andconifer regeneration. White marsh-marigold, pink and white mountain-heathers, and five-leaved bramble are common species in the herb layer. Themoss layer is a mix of heron’s-bill moss, red-stemmed feathermoss, lanky moss,and sphagnums. The 08 typically intergrades with the 06.

09 YcHm - Skunk cabbage is localized on lower wet seepage slopes anddepressions that have mineral seepage influence. Stands are scrubby and Hm/Ba dominated; Yc is much less common than on the same site association in theMHmm1. Low productivity reflects the saturated, cold, poorly aerated soils.Understory vegetation is lush and very diverse. Skunk cabbage, Indianhellebore, and rich-site indicators such as lady fern and oak fern are common.Leafy mosses and sphagnums dominate the moss layer. The 09 is often incomplex with 05 and 07 forests.

Non-forested site units: Two non-forested site units are described for the MHzone: Non-forested wetland (31) and Avalanche track (51). See page 5 •155 for descriptions.

MHmm2

5 • 163

MH

mm

2 L

and

scap

e P

rofi

lea

Site Units

5 • 164

aT

ree

sym

bols

are

def

ined

in

App

endi

x 3.

Sit

e S

erie

s

01 H

mB

a -

Blu

eber

ry

02 H

mB

a -

Mou

nta

in-h

eath

er

03 B

aHm

-O

ak f

ern

04 H

mB

a -

Bra

mbl

e

05 B

aHm

-T

wis

teds

talk

51 A

vala

nch

e tr

ack

06 H

mY

c -

Dee

r-ca

bbag

e

07 Y

cHm

-H

elle

bore

08 H

mY

c -

Sph

agn

um

09 Y

cHm

-S

kun

k ca

bbag

e

31 N

on-f

ores

ted

wet

lan

d

aR

elat

ive

and

actu

al S

MR

are

def

ined

in

App

endi

ces

6 an

d 7.

MHmm2

5 • 165

MH

mm

2 E

dat

opic

Gri

d

MHmm2 Site Series Flowchart

Site Units

5 • 166

NON-FORESTED


FRESH TO

MOIST FORESTSMoisture Regime 4-5.

Sites not clearly wet

or dry.

AVALANCHE

TRACKS

VERY MOIST TO


Seepage slopes and

depressions. Stands

generally of low to

poor productivity.

DRY TO FRESH


Upper slopes and

ridge crests.

Ericaceous shrubs, deer-cabbage, sedges, and 31sphagnum common. Non-forested

wetlands

Colluvial slopes on steep terrain. Sitka alder, 51willow, and salmonberry thickets. Ferns, Avalanche tracktwistedstalk, and Sitka valerian common.

Exposed rocky knolls. Very scrubby stands. 02Copperbush, mountain-heather and blueber- HmBa - Mountain-ries abundant. heather

Upper and mid slopes. Hm/Ba/Bl - blueberry - 01huckleberry forests of poor to medium HmBa - Blueberryproductivity. Rich-site indicators lacking.

Mid to lower slopes. Best forest growth in 03MHmm2. Ferns, twistedstalk, and foam- BaHm - Oak fernflower (rich-site indicators) common.

Very wet sites. Skunk cabbage abundant, 09rich-site indicators common; scattered sphag- YcHm - Skunknum. cabbage

Very wet sites. Skunk cabbage scattered; few 08rich-site indicators; copperbush, heathers, HmYc - Sphagnumand sphagnum abundant.

Wet sites. Skunk cabbage scattered or absent; 07deer-cabbage, Indian hellebore, and oak fern YcHm - Helleborescattered.

Wet sites. Skunk cabbage scattered or absent 06 HmYc - Deer-Deer-cabbage abundant. cabbage.

Poor- to medium-productivity forests. Soils 05gleyed. Rich-site indicators (devil’s club, BaHm -twistedstalk, lady fern, foamflower) common. Twistedstalk

Moderately productive forests. Soils freely 03drained. Abundant rich-site indicators (devil’s BaHm - Oak fernclub, green alder, oak fern, lady fern).

Poor-productivity Hm - blueberry forests. Soils 04subhygric. Few rich-site indicators. Herb HmBa - Bramblelayer moderately well developed.

Poor- to medium-productivity, mesic, Hm - 01blueberry forests. Few rich-site indicators; HmBa - Blueberryherb layer greatly reduced.

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MHmm2

5 • 167

MH

mm

2 V

eget

atio

n T

able

a

MHmm2 Environment Table


01 2-4/A-C upper - mid 10 - 75 C, Ov/C, (M)

02 0-1/A-C crest 0 - 60 Ov/R, Mv/R

03 2-4/D-E mid - toe 20 - 65 C, (Ov/R), (M)

04 5/A-C upper - mid 3 - 85 C, Cv/R, (M)

05 5/D-E mid - toe 9 - 85 C, (M)

06b 6/A-C crest - upper 10 - 35 M, (C)

07b 6/D-E upper - lower 30 - 60 C, (M)

08b 7/A-B lower 10 - 30 O

09 7/C-E lower 3 - 50 C, M

31 7/A-E upper - lower 5 - 60 O

51b 5-6/D-E upper - lower 5 - 85 C



Site Units

5 • 168

Humus formSoil soil depth (cm)particle sizea classificationa min-mean-max Important site features

Ls, K, (L) HFP, FHP, FO Mors Most common site series on mid to5 - 21- 48 upper slopes.

Ss, KL(s) HP, FO Mors Extremely exposed sites.10 - 21 - 37

Ls, KL, (L) HFP, (FO) Mors Freely drained, productive (for the MH3 - 18 - 42 zone) sites.

FLs, Ss FHP, HFP Mors Similar to 01 but greater seepage2 - 18 - 40 influence.

Ls G, HFP, R Mors Seepage sites. Gleyed soils limit(gleyed) 2 - 21 - 68 productivity.

L HFP; gleyed Mors Low-productivity forests in late snow10 - 15 - 25 areas.

FL, L G Mors Rooting and productivity limited by10 - 20 - 30 wet, cold soils.

-- M peaty “O” horizons Very wet, poor bog forests; limited> 60 cm extent.

S, KL G Mors, Moders Very wet, but mineral-rich swamp5 - 31 - 65 forests. Uncommon.

-- F peaty “O” horizons Non-forested wetlands. Soils too wet> 75 cm and cold for tree growth.

S, L R, DYB Moders Rich site conditions from colluvial1 - 6 - 13 mixing and deciduous litterfall.

MHmm2

5 • 169

MHwh 1Wet Hypermaritime Subzone

Windward Variant

Adjacent biogeoclimatic units: CWHvh2 occurs at lower elevations; MHmm1at similar elevations inland.



Zonal site series: Forest productivity in the MHwh is limited by the cold, wet,windy climate. As in the MHmm, the best zonal stands generally occur on steepcolluvial slopes with free drainage. (see notes on application of site classificationin the MH zone, page 5 • 153). The 03 site series is not described in this guide.It occurs only on base-rich parent materials, which are common on the QueenCharlotte Islands but not found on the mainland.

01 HmSs - Blueberry includes scrubby, but often dense, stands dominated byHm, Hw, Yc, and (Ss). In contrast to MHmm zonal sites, Ss may form a minorcomponent on MHwh1 zonal sites. These sites are common throughout thevariant on moderately well-drained (by hypermaritime standards) mid to upperslopes and crests. Shrub and herb layers are reduced due to the tight canopyclosure on these sites. Blueberry thickets will form in canopy gaps. The mosslayer is continuous and dominated by lanky moss; step moss, green sphagnum,and pipecleaner moss are also common.

Drier sites: One drier site series is recognized.

02 HwYc - Mountain-heather is restricted to crests and upper slope positionsthat have organic layers directly overlying rock or fragmental colluvium(Folisols). Severe exposure to wind is an important factor on these sites. Treesare very stunted and well spaced; Hm, Yc, (Cw), and (Ba) are common.Understory vegetation is well developed and distinctive. Mountain-heathers,blueberries, partridgefoot, fern-leaved goldthread, Pacific reedgrass, andheron’s-bill mosses are prominent.

Moist to wet sites: Six wetter site series are recognized.

04 HmYc - Goldthread forests occur on thin veneers (mostly colluvial andsaprolitic) on gentle to moderate seepage slopes. Tree growth is poor and forestsare scrubby; Yc and Hm are common. Shrub layers are poorly developed and arefloristically similar to zonal sites. Herb layers are sparse to moderatelydeveloped and characterized by fern-leaved goldthread, Pacific reedgrass, andfive-leaved bramble.05 YcHm - Twistedstalk occurs most commonly on steep slopes that receiveconstant seepage through thin colluvial veneers. The 05 represents the mostproductive forests in the variant; forests are still somewhat scrubby, but largerSs, Yc, and Hm may be found. Understory shrub composition is similar to thatin zonal forests, but the herb layer is much better developed, consisting oftwistedstalk, Pacific reedgrass, five-leaved bramble, and others. Leafy mossesare prevalent in the moss layer. Gleyed soils and a significant component of Ss

Site Units

5 • 170

in the canopy are characteristic features. Wetter sites usually have a componentof Indian hellebore, marsh-marigold, and deer-cabbage.

06 HmYc - Deer-cabbage occurs on broad ridge crests and gentle to moderateslopes where seepage moves slowly through thin mineral veneers, leading tosaturated conditions. Deer-cabbage and scattered sedges characterize the herblayer. The moss layer is dominantly lanky and step moss, but pipecleaner mossand sphagnum are also common. Forests on these sites are very scrubby andunproductive.

07 YcHm - Hellebore occupies similar topographic positions to the 06, but thenutrient regime appears to be richer in this site series. A greater abundance ofIndian hellebore and less deer-cabbage helps to distinguish the 07 from the 06.However, 06 and 07 forests often are found in a complex and can be difficult todistinguish. Low forest productivity is common to both units.

08 HmYc - Sphagnum bog forests of Hm and Yc typically grow on thickorganic blankets on level ridge crests or depressions. Forests are very scrubbyand open with a shrubby understory of copperbush, blueberries,mountain-heathers, and conifer regeneration. Mountain-heathers, goldthread,marsh-marigold, and skunk cabbage are common herbs. Although many sitestransitional between the 08 and the 09 are encountered, 08 tends to have lessskunk cabbage, fewer sedges, less leafy moss, and more sphagnum (as well as agreater diversity of sphagnum species) than does the 09.

09 YcHm - Skunk cabbage swamp forests are less common than bog forests(08). They occur in very wet, level areas with stagnant (usually mineral) soils.Trees are scrubby and well spaced; Yc, Hm, Hw, and Ba co-dominate. Herb andshrub layers are lush and diverse. Abundant sedges, skunk cabbage, Sitkavalerian, and leatherleaf saxifrage characterize this unit. See comments under 08.

Non-forested site units:

As in the hypermaritime CWHvh2 at lower elevations on the outer coast, openNon-forested wetlands (31) (mostly blanket bogs) are common in the MHwheven on some moderate to steep slopes. Richer wetlands (fens and marshes) arerare.

Avalanche tracks are much less characteristic ofthe MHwh than they are of the MHmm; noavalanche track unit is described.

MHwh1

5 • 171

MH

wh

1 L

and

scap

e P

rofi

lea

Site Units

5 • 172

aT

ree

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are

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ined

in

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e S

erie

s

01 H

mS

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Blu

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02 H

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03 S

sHm

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eedg

rass

(Qu

een

Ch

arlo

tte

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04 H

mY

c -

Gol

dth

read

05 Y

cHm

-T

wis

teds

talk

06 H

mY

c -

Dee

r-ca

bbag

e

07 Y

cHm

-H

elle

bore

08 H

mY

c -

Sph

agn

um

09 Y

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MHwh1

5 • 173

MH

wh

1 E

dat

opic

Gri

d

MHwh1 Site Series Flowchart

Site Units

5 • 174

NON-FORESTED


DRY TO FRESH


VERY MOIST TO


Seepage slopes and

depressions.

FRESH TO

MOIST FORESTSMoisture regime 4-5.

White marsh-marigold, deer-cabbage, western 31bog-laurel, sedges, and sphagnum common. Non-forested

wetland

Exposed rocky knolls. Mountain-heathers, 02partidgefoot, Pacific reedgrass, and heron’s bill HmYc - Mountain-moss prominent. heather

Hm-blueberry forests on upper to midslope 01colluvial (morainal, saprolitic) veneers. Herb HmSs - Blueberrylayer greatly reduced.

Very wet sites; mid/lower slopes, depressions. 09Skunk cabbage and sedges dominant. Green YcHm - Skunksphagnum and leafy mosses common. cabbage

Very wet sites; mid/lower slopes, depressions. 08Skunk cabbage and several sphagnum species HmYc - Sphagnumcommon; few sedges or leafy mosses.

Wet sites. Indian hellebore common; skunk 07cabbage scattered or absent. YcHm - Hellebore

Wet sites. Crests and gentle upper slopes. Little 06or no skunk cabbage; deer-cabbage and HmYc - Deer-sphagnums abundant. cabbage

Low- to poor-productivity forests; no Ss in 04canopy, herb layer moderately developed. HmYc -Lanky moss dominant. Goldthread

Productive forests (for MH zone). Often signifi- 05cant component of Ss in canopy. Herb layer YcHm -moderately developed; twistedstalk common. TwistedstalkLeafy mosses dominant.

Mesic Hm/Hw/Yc - blueberry forests. Herb 01layers greatly reduced. HmSs - Blueberry

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MHwh1

5 • 175

MH

wh

1 V

eget

atio

n T

able

a

MHwh1 Environment Table


01 2-4/A-C mid - crest 5 - 70 C, (M, Cv, Mv/R)

02b 0-1/A-C crest - upper 10 - 90 Ov/R, D

04 5/A-C mid - upper 15 - 55 Cv/R, Ov/R, Mv/R,D

05b 5/D-E lower - upper 20 - 60 Cv/R, Ov/R,(Mv/R)

06b 6/A-C lower - upper 10 - 30 Cv/R, Ov/R, Mv/R

07 6/D-E upper - mid 10 - 50 Cv/R, Ov/R, Mv/R

08b 7/A-B upper - mid 2 - 70 Ov/M, Ov/R

09b 7/C-E upper - mid 3 - 50 M

31b 7+/A-E all 0 - 25 O



Site Units

5 • 176

Humus formSoil Soil depth (cm)particle sizea classificationa min-mean-max Important site features

S(s), FHP, FO Mors Most common site series on mid toFL(s) - KL(s) 11 - 31- 80 upper slopes.

(f) FO Mors Extremely exposed, windy sites.8 - 9 - 10

KL - (FL) FHP, (G) Mors, (Moders) Similar to 01 but greater seepage6 - 15 - 34 influence.

FL G, FHP (gleyed) Mors (Moders) Relatively productive seepage sites.6 - 8 - 10

KL - (FL) G, FHP (gleyed) Mors Wet, stagnant soils limit productivity.6 - 10 - 14

FL, S FO, G, HP Mors Richer nutrient regime than 06 but wet,8 - 26 - 60 stagnant soils limit productivity.

KL, S F, M, G Mors Very wet, poor bog forests.1 - 8 - 15

S(s), KL G, M Mulls Very wet, but mineral-rich swamp5 - 34 - 65 forests; uncommon.

-- F, M peaty “O” horizons Non-forested wetlands; soils too wet>60 cm and cold for tree growth.

MHwh1

5 • 177

Site Units

5 • 178

5.6 SUB-BOREAL PINE – SPRUCE ZONE

The Sub-Boreal Pine – Spruce zone (SBPS) occupies a small area in thesoutheast part of the PRFR and is represented by only one subzone:

SBPSmc - Moist Cold subzone.

Much of this area has been classified from data collected in the Prince Georgeand Cariboo Forest Regions where the SBPS is more extensive. Ecosystemmapping at 1:50 000 has been completed for the SBPS in the PRFR andadjoining regions (Entiako Lake area) as part of a study examiningmanagement strategies and options for the Tweedsmuir - Entiako caribouwinter range (Cichowski and Banner 1993).

Description and differentiation of the biogeoclimatic units:PRFR - South: page 4 • 47

Interpretations:Wildlife: page 6 • 9Silviculture: page 7 • 68

Non-forested site units in the SBPS:

Non-forested wetlands dot the landscape of the SBPS and are one of itscharacteristic features. They are mostly mineral-rich fens and marshescharacterized by sedges, rushes, glow moss and fuzzy fen moss, but acidic,sphagnum-dominated bogs also occur. Roberts (1984) has produced acomprehensive guide to the wetland ecosystems of the SBPS in the CaribooForest Region, available from the Ministry of Forests, Forest Sciences Section,Williams Lake, B.C.

SBPS

5 • 179

SBPSmcMoist Cold Subzone

Adjacent biogeoclimatic units: SBSdk to the north; ESSFmc at higherelevations.



Zonal site series:

01 Pl - Feathermoss - Cladina occurs throughout the landscape on a widerange of slope positions and soil types. Pl is dominant and Sxw is often found inthe subcanopy. Shrub and herb layers are sparse and there is a moderatelydeveloped moss layer with a strong lichen component. Typical shrubs includesoopolallie, prickly rose, birch-leaved spirea, and common juniper. Typical herbsare bunchberry, kinnikinnick, twinflower, and dwarf blueberry.

Two phases are recognized: the Mesic phase (01a) with well- to imperfectlydrained, often fine-textured soils (Luvisols and Brunisols), and a better-developed moss layer with relatively few lichens; and the Submesic phase(01b) on well- to rapidly drained, usually coarse-textured Brunisols with morelichens and a lower cover of mosses.

Drier sites: Two drier forested site series are recognized (in addition to thesubmesic 01b described above).

02 Pl - Kinnikinnick - Cladonia is widespread in this zone, occurring ongravelly glaciofluvial terraces and eskers common to this region. Forests arestunted, open pine stands with a poorly developed understory. The site series isdistinguished by a dominance of lichens rather than mosses on the forest floorand an abundance of kinnikinnick in the herb layer. Soils are Brunisols orRegosols with a thin, crusty Mor humus form. These dry forests are often incomplex with non-forested wetlands (31, 32).

03 SbPl - Feathermoss is of limited extent in the SBPSmc. It is found on dry,north-facing slopes or in frost hollows. Forests have an overstory of Pl with asubcanopy of Sb, a sparse understory of Labrador tea, black huckleberry, andcrowberry, and a thick feathermoss carpet. The cold, nutrient-poor soils arewell- to moderately well-drained Brunisols or Luvisols with a relatively thickMor humus form. The abundance of Sb separates this unit from all othermore-or-less mesic units.

Fresh to wet sites: Four wetter forested site series are recognized.

04 Sxw - Scrub birch - Feathermoss is fairly abundant, occurring mostcommonly as a fringe surrounding wetlands. Sites are hummocky with poor-productivity Sxw, Pl, and (Sb) growing on elevated mounds. Lichens, crowberry,and bluejoint grow under trees on the drier mounds; scrub birch, willows, andglow moss occur in wetter swales. A perched water table is very common andsoils are usually gleyed. The 04 is distinguished from other site series bylacking rich-site indicators and having a mix of wet- and dry-site species. Thedrier 03 and 01 site series lack scrub birch, willows, and glow moss; wetter siteseries have higher cover of either horsetail or sphagnum.

Site Units

5 • 180

05 Sxw - Horsetail is the most productive site series in the SBPSmc. It is notwidespread, being restricted to areas adjacent to moving water. Labrador teaand scrub birch are absent; instead, black twinberry, highbush-cranberry, andmountain alder are common. Bluejoint and feathermosses are dominant. Soilsare fairly well-aerated Regosols, Brunisols, and Luvisols (often mottled), withloosely structured humus forms (usually Moders) or Ah horizons indicatingactive faunal decomposition. The 05 differs from the wetter 06 site series byhaving more Pl in the canopy and a lack of alder, willows, black currant,sphagnum, and sedges.

06 Sxw - Horsetail - Glow moss forests resemble the 05 but are more poorlydrained and generally not quite as productive for tree growth. They areuncommon, being found only in depressions or surrounding wetlands. Thevegetation is similar to that in the 05, except that more wet-site indicators suchas sedges, leafy moss and sphagnum moss are present. The soils are Gleysols orOrganics, with thick mucky organic horizons and water tables commonly foundwithin 20 cm of the soil surface.

07 Sb - Scrub birch - Sedge are forested bogs with very low nutrientavailability and distinctive bog vegetation. Stunted Sb with a ground cover ofLabrador tea, scrub birch, sedges, and sphagnum is typical. These ecosystemshave high water tables and Organic soils with poorly decomposed (fibric)material dominating the upper 40 cm. The 07 is arbitrarily separated fromNon-forested bogs (31) by having >10% tree cover.

Non-forested site units:

Non-forested bog (31) and Non-forested fen/marsh (32) ecosystems are acommon feature of the SBPS landscape and often occur in a complex with verydry pine - lichen forests (02) and wet, poor spruce forests (04 and 07) onglaciofluvial landforms. See other comments on page 5 • 179.

Seral Associations: No seral associations have been described for theSBPSmc. Because the SBPS has an extensive fire history, and successionproceeds slowly in this species-poor, dry, harsh environment, the concept of a“climax” association dominated by shade-tolerant species is not particularlyrelevant. Most immature stands are Pl-dominated, and can easily be classifiedinto site series using the stands’ current vegetation and site/soil characteristics.Seral communities dominated by At, willow, shrubs, or herbs may be moredifficult to classify, but are relatively uncommon.

SBPSmc

5 • 181

SB

PS

mc

Lan

dsc

ape

Pro

file

a

Site Units

5 • 182

aT

ree

sym

bols

are

def

ined

in

App

endi

x 3.

Sit

e S

erie

s

01P

l -

Fea

ther

mos

s -

Cla

din

a

02P

l -

Kin

nik

inn

ick

-C

lado

nia

03S

bPl

-F

eath

erm

oss

04S

xw -

Scr

ub

birc

h -

Fea

ther

mos

s

05S

xw -

Hor

seta

il

06S

xw -

Hor

seta

il -

Glo

w m

oss

07S

b -

Scr

ub

birc

h -

Sed

ge (F

ores

ted

bog)

31 N

on-f

ores

ted

bog

32 N

on-f

ores

ted

fen

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sh

a R

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and

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SBPSmc

5 • 183

SB

PS

mc

Ed

atop

ic G

rid

Clic

k he

re to

con

tinue

to p

age

5-18

4

SBPSmc Site Series Flowchart

Site Units

5 • 184

NON-FORESTED


Depressional areas.

MOIST TO WET


Level/depressional

areas; seepage

slopes. Sites with

saturated soils.

Gleysols or Organics.

SLIGHTLY DRY

TO FRESH


Sites neither very

dry or very wet.

DRY FORESTSMoisture regime 0-4.

Most commonly on

very coarse, glacio-

fluvial terraces or on

ridge crests/upper

slopes.

Site dominated by sphagnum, Labrador tea, 31 Non-forestedand other Ericaceous shrubs. bog

Sedges and willows dominate; sphagnum 32 Non-forestedmixed with other mosses. fen/marsh

Very dry sites; Open Pl forest. Kinnikinnick 02abundant. Sparse shrub and herb layer. Lichens Pl - Kinnikinnick -dominate moss layer.

Nutrient-poor, dry sites on cold aspects. Gla- 03ciofluvial flats or coarse, midslope morainal till. SbPl -Pl forest with Sb subcanopy; Sxw infrequent. FeathermossLabrador tea abundant.

Dry Pl/Sxw stands with moderate growth. No 01bSb or Labrador tea. Kinnikinnick, dwarf Pl - Feathermoss - blueberry, soopolallie common. Cladina;

submesic phase

Low-productivity Sb. Labrador tea, willows, 07crowberry, and Sitka sedge common. Sphag- Sb - Labrador tea -num dominates moss layer. Organic soils. Sphagnum

Pl/Sxw with poor growth. Scrub birch and 04crowberry abundant. Lichens and feather- Sxw - Scrub birchmosses co-dominate. Cold, poorly drained - Feathermossmineral soils. Often adjacent to wetlands.

Sxw forests with poor to moderate growth. 06Horsetails, mountain alder, oak fern, and soft- Sxw - Horsetail -leaved sedge abundant. Leafy, glow, and Glow mosssphagnum mosses common. Gleysols orOrganic soils.

Sxw/Pl forests with good growth. Horsetails 05abundant. Few sedges. Moss layer dominated Sxw - Horsetailby feathermosses. Mottled soils.

Sx/Pl forests with good growth. Horsetails 05abundant. Soils mottled. Sxw - Horsetail

Subhygric sites. Stunted Pl/Sxw dominant. 04Scrub birch abundant; glow moss present. Sxw - Scrub birchCold, imperfectly drained soils; soils mottled. - feathermoss

Mesic Pl forests with Sb subcanopy; Sxw 03infrequent. Labrador tea abundant. Cold, SbPl -well-drained, nutrient-poor soils. Glaciofluvial Feathermossflats or coarse midslope morainal till.

Mesic sites. Pl/Sxw stands with moderate 01agrowth. No Sb or Labrador tea. Kinnikinnick, Pl - Feathermoss -dwarf blueberry, and soopolallie common. Cladina;

mesic phase

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SBPSmc

5 • 185

SB

PS

mc

Veg

etat

ion

Tab

lea

SBPSmc Environment Table


01 a) Mesic 4-5/B-C upper - lower (level) 0 - 55 M, FGv/M

01 b) Submesic 3-4/B-C upper - mid (level) 0 - 65 FG, M, (L)

02 1-2/A-B level, crest - mid 0 - 45 FG, (Mv/R, Cv/R)

03 3-4/A-B mid or level 0 - 20 M, FG

04 5-6/A-B lower - toe 0 - 5 M

05 (4)-6/C-E lower - toe 0 - 15 F, (FG, L)

06 6-7/C-(E) toe - depressions 0 - 10 M, Ov/M, L

07b 7/A-B level, depressions 0 O

31b 7+/A-B depressions, level 0 O

32b 7+/B-C depressions, level 0 O



Site Units

5 • 186


C - Ss GL, DYB, (HFP) Mors Subsoil often compacted. Summer3 - 7 - 12 moisture deficits occur.

KL - Ss DYB, GL Mors Pronounced summer moisture deficits.1 - 5 - 14

S - Ss DYB, (R) Mors Very dry, poor soils. Often on0 - 2 - 4 glaciofluvial eskers.

KL - Ss DYB, GL Mors Cold, well-drained soils. Usually north3 - 8 - 13 and east aspects.

L - Ls GL, DYB, G; Mors Cold, imperfectly to poorly drained(gleyed) 5 - 8 - 13 soils. Often compacted gravels.

FL - S R, DYB, GL; Moders, Mors Usually along major streams. Season-(gleyed) 6 - 11- 18 ally fluctuating water tables.

FL - C G, F, M Mors, Moders High water tables. Poorly aerated soils.9 - 27 - 45

-- F, M, H peaty “O” horizons Acidic, nutrient-poor organic peats.> 60cm

-- F, M peaty “O” horizons Non-forested bogs. Soils too wet for> 1 m tree growth. Frost pockets.

-- M, H, G peaty “O” horizons Non-forested fens/marshes. Soils too> 40 cm wet for tree growth.

SBPSmc

5 • 187

Site Units

5 • 188

5.7 SUB-BOREAL SPRUCE ZONEThe Sub-Boreal Spruce Zone (SBS) in the PRFR has been subdivided into thefollowing biogeoclimatic units:

SBSdk - Dry Cool subzone

SBSmc - Moist Cold subzoneSBSmc2 - Babine variant

SBSwk - Wet Cool subzoneSBSwk3 - Takla variant

The SBSwk3 is found along the eastern fringe of the region east of Babine Lake.Because of its limited extent, this subzone is not described in this guide. Acomplete description is found in MacKinnon et al. (1990).

Description and differentiation of biogeoclimatic units:PRFR - South : page 4 • 55PRFR - North : page 4 • 89

Interpretations:Wildlife: page 6 • 9Silviculture: page 7 • 70

Non-forested site units in the SBS:

Non-forested sites at both ends of the moisture spectrum are described for theSBS: two wetland and two dry grassland/scrub site series.

Wetland ecosystems are localized in the zone; dry to moist interior climates andthe predominance of well-drained morainal blankets provide limited locationssuitable for wetland formation. Small Fens are the most common wetland typeforming in depressions and along sluggish stream channels. These fens aredominated by willows and sedges. Sedge-derived peat >1 m in depth is typical.Marshes are restricted to lake edges and are most common in the BulkleyValley (SBSdk). These sites are very rich and are dominated by cattails andbulrushes. Bogs are found in depressional areas often subject to cold airdrainage. Bogs are rare or lacking in the SBSmc2, but occur in the SBSdk.These sites have a distinctive floral composition dominated by sphagnum,Labrador tea, and other ericaceous shrubs.

Grassland/scrub is limited to the drier climates of the SBSdk and the lowestelevations and most southerly exposures of the SBSmc2. Saskatoon - Slenderwheatgrass scrub/steppe ecosystems occur on dry rocky sites with favourablewarm aspects over base-rich parent materials. The habitat is too dry for full-grown trees; instead there is a mosaic of “scrub” and “steppe” (grassland). Shrub species include saskatoon, common snowberry, Rocky Mountain juniper,chokecherry, prickly rose, and stunted At. Bluegrass - Slender wheatgrassgrasslands are rare in the SBSdk today as most have been converted to haypastures. Originally they probably covered extensive areas on warm aspects inthe Bulkley Valley and Ootsa Lake country. In this unit, trees, shrubs, andmosses are absent. Herb layers are well developed in both units with a diversityof grasses and forbs. Soils include Brunisols, Luvisols, and some Chernozems.

SBS

5 • 189

SBSdkDry Cool Subzone

Adjacent biogeoclimatic units: SBSmc2 at higher elevations and to thenorth; SBPSmc at the southern edge of the PRFR; ICHmc2 to the west.

Elevation range: 500 - 750 m in the north; 700 - 1100 m in the south.


Zonal site series:

01 Sxw - Spirea - Purple peavine is widespread throughout the subzone andcovers more area than any other site series. It is found on a wide range ofparent materials, but most often on deep morainal deposits. Although Sxw isthe climax tree species, most mature stands also have some Pl or At. The shrublayer is moderately developed and diverse with prickly rose, birch-leaved spirea,soopolallie, and Sxw dominant. Characteristic herbs are purple peavine, showyaster, bunchberry, and fireweed. The moss layer is not as well developed asSBSmc2 zonal sites because of the lusher shrub and herb layers. Two phasesare recognized: a Fine-textured phase (01a) on moderately well- to imperfectly drained Luvisols with loamy to clayey particle sizes; and a Coarse-textured phase (01b) on well- to rapidly drained Brunisols with coarse loamy,often skeletal particle sizes.

Drier sites: Drier-than-mesic ecosystems are widespread in the SBSdk. Sixforested site series have been described.

02 Pl - Juniper - Ricegrass is restricted to the driest, most nutrient-poor rockoutcrops and gravelly terraces. Pl forms open, poorly growing stands with asparse understory of mainly Pl regeneration, common juniper, and kinnikinnick.The moss layer is dominated by reindeer lichens. Soils are coarse-texturedBrunisols with a thin, crusty Mor humus.

03 Pl - Feathermoss - Cladina site series is moister and more productive, andhas greater species diversity than the 02. It is also more common. The 03 occursmainly on gravelly glaciofluvial deposits or bedrock outcrops. Pl dominatesthese fairly open stands. Shrub and herb layers are sparse. It is most clearlydistinguished from the 02 by the dominance of red-stemmed feathermoss in themoss layer. Other site units lack kinnikinnick and are not dominated by poorlygrowing Pl.

04 Fd - Soopolallie - Feathermoss is mainly localized along the eastern endsof Francois and Babine lakes, usually on relatively steep, dry, south-facingslopes. Fd is the indicator species for this site series, often occurring as veteransof past fires. Fd occurs with Sxw and some Pl, At, and Ep. The shrub layer isdominated by soopolallie, with birch-leaved spirea, prickly rose, and saskatooncommon. Soils are shallow, often containing cobbles and stones derived fromvolcanic bedrock.

05 Sxw - Spirea - Feathermoss is slightly drier and less productive than thezonal site series. These ecosystems are widespread in the drier, southernportion of the SBSdk (southern Lakes Forest District), but scattered elsewhere.The vegetation is similar to that in the 01, but tree growth is slightly poorer,shrub and herb layers are less developed and vigorous, and mosses are more

Site Units

5 • 190

prominent. Soils have more rapid drainage than do soils in the 01 site series,and usually thinner forest floors.

Fresh to wet sites: Five wetter forested site series are recognized.

06 Sxw - Twinberry - Coltsfoot is abundant in the northern SBSdk, butbecomes less common to the southeast. It develops in habitats that are slightlymoister and richer than the 01. Growth of Sxw, Pl, and At is better thanaverage. Understory species composition is very similar to that on zonal sites,but shrub layers are more vigorous. Prickly rose, highbush-cranberry,thimbleberry, and red-osier dogwood dominate. Finer-textured soils may showmottling or gleying at depth.

07 Sxw - Horsetail is common but not abundant on moist to wet sitesthroughout the subzone. Mature stands have large, widely spaced Sx and Pl,with deciduous trees present in younger stands. Shrub and herb layers are welldeveloped. The 07 is differentiated from other site series by the presence ofhorsetails in the herb layer. Two soil phases are recognized. The productiveFreely drained phase (07a) occurs on coarse, inactive fluvium; soils areyouthful and may have some Ah development. The Poorly drained phase(07b) occurs on finer-textured lacustrine deposits with high water tables. Theseare less productive, swampy ecosystems.

08 Act - Dogwood - Prickly rose occurs on active floodplains adjacent tomajor rivers. Shrub layers are tall and vigorous with red-osier dogwood, alders,and willows present, as well as the typical complex of moist-site shrubs. Theherb layer characteristically includes bluejoint, American vetch, blue wild-rye,sweet-cicely, and palmate coltsfoot. Mosses are sparse or lacking. Soils areRegosols and Brunisols with thin, loose litter layers; they generally showevidence of repeated flooding (cumulic horizons).

09 Sb - Creeping-snowberry - Sphagnum represents forested bogs that arescattered throughout the subzone on depressional sites. These bogs have a verydistinctive vegetation of poorly growing or stunted black spruce with a groundcover of Labrador tea, creeping-snowberry, and bog cranberry. The moss layer isdominated by sphagnum, but has a diversity of lichens as well. Organic soils aretypical.

10 Sb - Soft-leaved sedge - Sphagnum forested swamps differ from forestedbogs (09 site series) in that subsurface water flows through the ecosystem,providing aeration and nutrients. Forested swamps have >10% cover of scrubbySb and Sxw and patches of scrub birch, willows, alders, red-osier dogwood, andLabrador tea. The herb layer is dominated by sedges and horsetails. The mosslayer includes a variety of rich-site mosses (fuzzy fen moss, sickle mosses, andleafy mosses) as well as sphagnum. Soils are saturated Organics.

Non-forested site units: Four generalized non-forested units have beendescribed for the SBSdk: Non-forested bog (31), Non-forested fen/marsh(32), Saskatoon - Slender wheatgrass scrub/steppe (81), and Bluegrass -Slender wheatgrass grasslands (82). See page 5 • 189 for brief descriptionsof these units.

Seral associations: Human activity (agriculture, settlement, logging, burning)and wildfire have affected all parts of the SBSdk. As a result, much of thelandscape is in early to mid seral stages. Some preliminary work towardsdeveloping a classification of seral associations, ranging from shrub-herb stagesto mature deciduous and mixedwood forest, has been ongoing, but this seralclassification is not included in the field guide.

SBSdk

5 • 191

SB

Sd

k L

and

scap

e P

rofi

lea

Site Units

5 • 192

aT

ree

sym

bols

are

def

ined

in

App

endi

x 3.

Sit

e S

erie

s

01 S

xw -

Spi

rea

Pu

rple

pea

vin

e

02 P

l -

Jun

iper

-R

iceg

rass

81 S

aska

toon

-S

len

der

wh

eatg

rass

(scr

ub/

step

pe)

03 P

l -

Fea

ther

mos

s -

Cla

din

a

04 F

d -

Soo

pola

llie

-F

eath

erm

oss

82 B

lueg

rass

-S

len

der

wh

eatg

rass

(Gra

ssla

nd)

05 S

xw -

Spi

rea

-F

eath

erm

oss

06 S

xw -

Tw

inbe

rry

-C

olts

foot

07 S

xw -

Hor

seta

il

08 A

ct -

Dog

woo

d -

Pri

ckly

ros

e (F

lood

plai

n)

09 S

b -

Cre

epin

g-sn

owbe

rry

-S

phag

nu

m (F

ores

ted

bog)

10 S

b -

Sof

t-le

aved

sed

ge -

Sph

agn

um

(For

este

d sw

amp)

31 N

on-f

ores

ted

bog

32 N

on-f

ores

ted

fen

/mar

sh

aR

elat

ive

and

actu

al S

MR

are

def

ined

in

App

endi

ces

6 an

d 7.

SBSdk

5 • 193

SB

Sd

k E

dat

opic

Gri

d

SBSdk Site Series Flowchart

Site Units

5 • 194

NON-FORESTED


NON-FORESTED

GRASSLANDS

DRY FORESTSMoisture regime 0-3.

Usually on ridge

crests, upper slopes,

or terraces; thin and/

or coarse soils. Pl orFd forests.

VERY MOIST TO


Sites with saturated

soils. Gleysols or

Organics

FLOODPLAIN

FORESTS

Sites dominated by sphagnum, Labrador tea, 31and other ericaceous shrubs. Non-forested bog

Sedges and willow dominant vegetation; 32 Non-forestedsphagnum not clearly dominant. fen/marsh

See introductory text, page 5 • 189. 81, 82

Act-dominated forests; thick shrubby under- 08story. Dogwood dominant shrub. Regosols or Act - Dogwood -Brunisols. Prickly rose

Xerix sites; open Pl with low productivity. 01Kinnikinnick, common juniper abundant. Pl - Juniper -Sparse shrub and herb layer. Lichens dominate Ricegrassmoss layer.

Xeric sites. Dense Pl with poor productivity; 03common juniper infrequent; lichens common Pl - Feathermoss -but not dominant. Very coarse and gravelly Cladinasoils

Open Fd-dominated forests; Soopolallie 04abundant. Lichens uncommon. Thin soil Fd - Soopolallie -veneers over rock. Eastern SBSdk only. Feathermoss

Poor to medium Pl, Sxw, (Fd) forests. Li- 05chens uncommon; no Pl regeneration. Sxw - Spirea -Coarse, well-drained soils. Feathermoss

Sxw forests with good growth. Horsetails 07abundant; leafy mosses common. Swx - Horsetail

Open Sb forests with stunted growth; wil- 09 Sb - Creeping -lows, Labrador tea, mountain alder, and sedges snowberry -abundant. Sphagnum dominates moss layers. Sphagnum

Sb, Sxw forests with poor growth. Horsetails, 10soft-leaved sedge, and fuzzy fen moss abun- Sb - Soft-leaveddant. sedge - Sphagnum

Pl/Sxw forests with good growth. Well-devel- 06oped and diverse shrub layer; thimbleberry Sxw - Twinberry -abundant.

Sxw forests with good growth. Well-developed 07shrub layer; no thimbleberry; horsetails Swx - Horsetailabundant; leafy mosses common.

Pl/Sxw (Fd) forests with poor to moderate 05 Sxw - Spirea -growth. Coarse, well-drained soils. Feathermoss

Sxw/Pl (At) with moderate growth; shrub and 01herb layers moderately developed; some rich Sxw - Spirea -site indicators with minor cover. Purple peavine

DRY TO MOIST


Stands not noticeably

very dry or very wet.

Tree growth poor to

good.

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➔

➔

➔

➔

➔

➔

➔

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➔

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➔

➔

➔

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SBSdk

5 • 195

SB

Sd

k V

eget

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n T

able

a

SBSdk Environment TableSoil

Site moisture/ Slope %series Phase nutrients Slope position range Parent materiala

01 a) Fine (3)-5/C-D all 0 - 75 M, (F, C, L, Mv/R)textured

01 b) Coarse 3-4/B-D all, mainly mid 0 - 75 M, FG, Mv/R, Ctextured

02b 1/A-B crest - upper 0 - 30 Mv/R, Cv/R, FG

03 2/A-C level, crest - upper 0 - 20 FG, M, (Cv/R,Mv/R)

04 2-3/C-D crest - lower 0 - 65 Cv/R, Mv/R

05 3-4/(A)-C all 0 - 40 M, FG, (C)

06 4-5/(C)-E all 0 - 40 M (F, L, C)

07 a) Freely 5/D-E level 0 - 10 F, Mdrained

07 b) Poorly 5-6/C-D level, depressions 0 - 2 L, Lv/Mdrained

08 5-6/D-E level 0 F

09 6-7/A-B depressions, level 0 O

10 6-7/C-E level, depressions 0 O, Ov/L

31 7+/A-B depressions, level 0 O

32 7+/C-E depressions, level 0 O

81 1-2/C-E upper - mid 20 - 80 Cv/R, M/R,C/M

82 2-3/D-E upper - level 0 - 35 M, L

a Codes are described in Section 3.2.2, page 3 • 8. b Limited data; unit is described from fewer than three plots.

Site Units

5 • 196


FL, FC GL Mors, Moders Clay-rich Bt layer may restrict rooting.3 - 9 - 16

KL, Ss DYB, GL Mors, (Moders) Often gravelly. Deep rooting.1 - 6 - 13

KL, Ss DYB, EB, HFP Mors Driest, most rapidly drained sites.1 - 2 - 3

KL, Ss DYB Mors Often gravelly or stony.1 - 4 - 9

KL, Ls DYB, EB, GL Mors Mainly on south-facing slopes above3 - 6 - 9 eastern Francois and Babine lakes.

FL, KL, S DYB, GL Mors Less productive than 01. Moisture3 - 8 - 15 deficits during growing season.

FL, CL, (S) GL, DYB, EB Mors, Moders Mottles often present in Bt layer.(gleyed) 4 - 8 - 19

FL, Ss DYB, SB, GL Moders Seasonally fluctuating water tables but7 - 11 - 16 free drainage.

variable HG Moders Consistently high water tables, poorFC, S 9 - 13 - 16 soil aeration.

KL, S R, DYB Moders Active floodplains. Annual flooding.5 - 4 - 8

-- F, M, H peaty “O” horizons Permanently high water table.> 60 cm Sphagnum-derived peat.

-- M, (F, G) peaty “O” horizons Permanently high water table. Sedge/> 60 cm moss-derived peat or mineral soils.

-- M, F peaty “O” horizons Non-forested bog. Soils too wet and > 1 m cold for tree growth.

-- M, F, G peaty “O” horizons Non-forested fen/marsh. Soils too wet> 1 m and cold for tree growth.

FL, Ls MB, SB, EB, GL Mulls Rare. Steep S/SW aspects on base-rich0 - .5 - 1 bedrock.

FL MB, GL Mulls Rare. Usually S to W aspects..5 - .8 - 1

SBSdk

5 • 197

SBSmc2Moist Cold Subzone

Babine Variant

Adjacent biogeoclimatic units: SBSdk at lower elevations; SBSwk3 to theeast of Babine Lake near the boundary with the Prince George Forest Region;ESSFmc at higher elevations; ICHmc2 to the west.

Elevation range: 850 - 1350 m in south; 500 - 1050 m in north.


Zonal site series:

01 Sxw - Huckleberry occupies a wide variety of landforms and slopepositions, but is most often found on deep blankets of glacial till. Mature standsare mixtures of Pl, Bl, and Sxw with abundant Bl regeneration. The main shrubspecies is black huckleberry. Bunchberry, five-leaved bramble, twinflower, andheart-leaved arnica dominate the herb layer. Feathermosses (red-stemmedfeathermoss, step moss, knight’s plume) carpet the forest floor.

Three phases are recognized: a Mesic, fine-textured phase (01a); a Mesic,coarse-textured phase (01b); and a Submesic phase (01c). The 01c has arelatively sparse feathermoss-dominated understory and lower productivitythan 01a and 01b.

03 SbPl - Feathermoss forests are found on cold, nutrient-poor sites with amore-or-less mesic moisture regime. These are often mid to lower, north-facingslopes that receive cold air drainage. Pl is the dominant tree species, but thereis always a significant component of Sb. Poor-site indicators such as Labradortea, dwarf blueberry, creeping-snowberry, and bastard toad-flax are common.Soils are typically moderately well- to imperfectly drained Luvisols with a root-restricting Bt layer. This site series is uncommon over most of the variant.

Drier sites: Only one drier forested site series has been distinguished (inaddition to the Submesic 01c described above).

02 Pl - Huckleberry - Cladonia occupies the driest and often poorest sites inthe subzone. It is relatively rare in the northwest, but more common in thedrier, southern parts of the subzone. These are usually pure stands of small Pl,with Bl and Pl in the understory. Sites usually have scattered black huckleberryand soopolallie, and dwarf woody plants such as kinnikinnick, twinflower,prince’s-pine, and dwarf blueberry. The abundance of reindeer and cladonialichens on the forest floor distinguishes this site series from all others. Soils areskeletal or shallow.

Fresh to wet sites: Six wetter forested site series have been described.

05 Sxw - Twinberry - Coltsfoot is found on moist mid- and lower-slopepositions, often on warm, south aspects. The stands are open and usually havesome deciduous trees. Shrub and herb layers are generally more diverse andvigorous than those of any other SBSmc2 site series except perhaps the 09.Thimbleberry is the typical dominant shrub. Oak fern is absent or very rare,differentiating this unit from the 06 site series. Feathermosses dominate. Soilsoften have an Ah horizon.

Site Units

5 • 198

06 Sxw - Oak fern occurs on sites with similar moisture and nutrientconditions to the 05 site series, but is distinguished by the abundance of oakfern and a lower diversity of shrubs and herbs. Scattered devil’s club issometimes present. This site series occurs throughout the subzone, but is mostabundant in areas of moister local climate. Soils on these sites often have acompacted layer and seepage present within 40 - 80 cm of the surface.

07 Sxw - Scrub birch - Feathermoss is limited in extent in this variant; it isusually found bordering fens and bogs. These are nutrient-poor, often cold siteswith restricted rooting over a perched water table. Growth of Pl, Sxw (and Sb) isfair to poor, and the shrub layer is not vigorous. The presence of shrub species,such as scrub birch, willow, and black twinberry, and the abundance of glowmoss are characteristic of this site series. The soils are gleyed Luvisols witheither a compacted gravelly layer or a dense clayey layer not far beneath thesurface.

09 Sxw - Devil’s club ecosystems are almost always found on lower or toeslopes, or in gullies, and are best developed on north-facing slopes. This siteseries is most common in the mountainous, western portions of the SBSmc2along ephemeral streams (Fluvial phase 09a) or on seepage slopes (Morainalphase 09b). Devil’s club is the characteristic dominant shrub; thimbleberry,prickly gooseberry, oak fern, clasping twistedstalk, sweet-scented bedstraw, andfoamflower are common associates. The moss layer is patchy with leafy mossesand feathermosses co-dominating.

10 Sxw - Horsetail occurs on lower slopes, depressions, valley floors, andadjacent to bodies of water. Mature trees (Sxw, Bl, minor Pl) are large andwidely spaced. In the shrub layer, mountain alder, black twinberry, pricklygooseberry, and highbush-cranberry are characteristic. Horsetails are thedominant herbs and their abundance distinguishes this unit from all other siteseries. The forest floor is usually mounded with leafy, ragged, and glow mossesin wet hollows and feathermosses on drier mounds. Two phases are recognized:the Fluvial phase (10a), which occurs on level sites adjacent to streams; andthe Lacustrine/morainal phase (10b), which occurs on poorly draineddepressions and level sites.

12 SbSxw - Scrub birch - Sedge swamp forests occupy low-lying positions inthe landscape and are often associated with frost pockets. They are variable inspecies composition, but have a distinctive appearance. Clumps of poorlygrowing Sb and Sw are interspersed with shrubs such as willow,highbush-cranberry, scrub birch, black twinberry, hardhack, and Labrador tea.The herb layer is diverse and dominated by sedges. The moss layer is awell-developed mixture of sphagnum, golden fuzzy fen moss, glow moss, andleafy mosses. Soils are Organics or occasionally Gleysols, with the water tableoften within 10 cm of the soil surface.

Non-forested site units: Non-forested wetlands occur throughout the SBSmc2but are confined to depressions in the morainal landscape. These wetlands arealmost exclusively nutrient-medium to nutrient-rich fens and marshes(SBSmc2/31). Acidic bogs are rare to non-existent. See page 5 • 189 forgeneralized descriptions of SBS wetlands.

Seral Associations: Early to mid seral ecosystems are widespread in theSBSmc2 because of frequent wildfire and extensive human activity, mainlylogging. There has been some preliminary work towards developing aclassification of seral associations, ranging from shrub-herb stages to maturedeciduous and mixedwood forest, but these are not included in the field guide.

SBSmc2

5 • 199

SB

Sm

c2 L

and

scap

e P

rofi

lea

Site Units

5 • 200

aT

ree

sym

bols

are

def

ined

in

App

endi

x 3.

Sit

e S

erie

s

01S

xw -

Hu

ckle

berr

y

02P

l -

Hu

ckle

berr

y -

Cla

don

ia

03S

bPl

-F

eath

erm

oss

05S

xw -

Tw

inbe

rry

-C

olts

foot

06S

xw -

Oak

fer

n

07S

xw -

Scr

ub

birc

h -

Fea

ther

mos

s

09S

xw -

Dev

il’s

clu

b

10S

xw -

Hor

seta

il

12S

bSxw

-S

cru

b bi

rch

-S

edge

(For

este

d sw

amp)

31N

on-f

ores

ted

fen

/mar

sh

Not

e: S

ite

Ser

ies

04, 0

8, a

nd

11 o

ccu

r in

th

e P

rin

ce G

eorg

e an

dC

arib

oo r

egio

ns

only

an

d ar

e n

ot p

ortr

ayed

on

th

is g

rid.

aR

elat

ive

and

actu

al S

MR

are

def

ined

in

App

endi

ces

6 an

d 7.

SBSmc2

5 • 201

SB

Sm

c2 E

dat

opic

Gri

d

SBSmc2 Site Series Flowchart

Site Units

5 • 202

NON-FORESTED


DRY FORESTSMoisture regime 0-3.Usually on ridgecrests or upper slopes;thin and/or coarsesoils. Pl dominanttree species.

VERY MOIST TO

WET FORESTSMoisture regime 6-7.Sites with standingwater or saturatedconditions. Soils areGleysols or Organics.

FRESH TO

MOIST AND

POOR FORESTSMoisture regime 4-5;Nutrient regime A-B.Sb present incanopy.

FRESH TO

MOIST AND

MEDIUM TO

RICH FORESTSMoisture regime 4-5;Nutrient regime C-E.Sites with moderateto good tree growth.Mid to lower slopes.

Sedges/grasses and willows dominant. 31Sphagnum, glow moss, and fuzzy fen moss co- Non-forested fen/dominate moss layer. marsh

Driest forested sites. Kinnikinnick common. 02Sparse shrub and herb layer. Lichens co- Pl - Kinnikinnick -dominate moss layer. Cladonia

Poor sites. Sb common. Labrador tea, black 03 SbPl -huckleberry, and dwarf blueberry common in Feathermossshrub layer. Feathermosses dominant.

Submesic ecosystems on coarse-textured or 01cshallow soils or upper slopes. Pl/Bl co-domin- Sxw - Huckle-nant; moderate productivity. Feathermosses berry;dominate. submesic phase

Large Sxw/(Bl) growing on elevated micro- 10sites; no Sb. Horsetails abundant; leafy Sxw - Horsetailmosses abundant; lady fern frequent. Sitestypically hummocked.

Stunted and sparsely distributed Sb and Sxw. 12Willows, scrub birch, alder, and sedges abun- SbSxw - Scrubdant. Sphagnum and golden fuzzy fen mosses birch - Sedgedominate moss layer. Organic soils.

Pl, Bl, Sxw, (Sb) with poor growth. Feather- 07mosses dominate. Gleysols or gleyed sub- Sxw - Scrub birchgroups. Perched water table. - Feathermoss

Labrador tea, black huckleberry, dwarf blue- 03 SbPl - berry, bunchberry, and creeping-snowberry Feathermossabundant; feathermosses dominant. Soils areGrey Luvisols or Brunisols, sometimes mottled.

Shrub layer diverse, but dominantly black 07huckleberry; feathermosses, glow moss, and Sxw - Scrub birchsphagnum co-dominate. Poorly drained gleyed - Feathermosssoils.

Devil’s club abundant. Oak fern prevalent; 09 Sxw - Devil’sleafy mosses abundant. club

Oak fern dominates herb layer; devil’s club 06scattered; five-leaved bramble common. Sxw - Oak fern

Shrub/herb layers diverse and well developed. 05No devil’s club; thimbleberry and twinberry Sxw - Twinberry -abundant; leafy mosses uncommon. Coltsfoot.

Black huckleberry and Bl regeneration dominate 01a/01bshrub layers. Few rich- or wet-site indicators. Sxw - Huckleberry

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5 • 203

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SBSmc2 Environment TableSoil

Site moisture/ Slope %series Phase nutrients Slope position range Parent materiala

01 a) Mesic, 4/C-(D) crest - lower (level) 0 - 45 M, (L)Finetextured

01 b) Mesic, 4/B-C crest - lower (level) 0 - 40 M, FG, (F, Mv/R)Coarsetextured

01 c) Submesic 3/B-D crest - lower (level) 0 - 50 M, C, FG, Mv/R,Cv/R (L)

02 1-3/A-(C) level; crest - upper 0 - 30 FG, Mv/R, Cv/R

03 3-5/A-B level; upper - lower 0 - 5 M, FG

05 4-5/(C)-E upper - toe 2 - 50 M, F, C

06 4-5/C-D mid - toe (upper) 1 - 60 M, Cv/M, (L)

07b 5-6/A-B lower - depressions 0 - 15 M, FG, L

09 a) Fluvial 5/D-E lower - toe 2 - 56 F (FG)

09 b) Morainal 5-6/D-E mid - toe 2 - 56 Mb, Cv/M

10 a) Fluvial 5-6/C-E level, depressions 0 - 4 F, Fv/M

l0b b) Lacustrine 6-7/C-E toe - depressions 0 - 10 L, M, Ov/L/Morainal

12 7/B-E depressions, level 0 O, Ov/F, Ov/L

31b 7+/B-E depressions, level 0 O

a Codes are described in Section 3.2.2, page 3 • 8.b Limited data; unit described from fewer than three plots.

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L - C GL, DYB, (HFP) Mors, (Moders) Compact Bt layer may restrict rooting.3 - 8 - 16

KLs - Ss DYB, GL, (HFP) Mors Often gravelly; deep rooting.2 - 8 - 16

FL - Ss DYB, GL, (HFP) Mors Sites experience some moisture1 - 5 - 9 deficits.

KLs - Ss DYB, (HFP) Mors Very dry, poor soils. Xeromors2 - 4 - 9 common.

KL - FL GL, (DYB, SB) Mors Cold, acidic soils; shallow rooting.5 - 7 - 10 North and east aspects.

S - FL (s) GL, DYB Moders, Mors Ah horizon often present.6 - 12 - 22

FC - Ls GL, DYB, SB Moders, Mors Seepage may be present within 40 cmoften gleyed 1 - 9 - 14 of the surface.

FL - KLs G, GL (gleyed) Mors, Moders Perched water table. Often in frost15 - 25 - 35 pockets.

FL - Ss EB, DYB Mors, Moders Freely drained. Seasonally fluctuatingl0 - 20 - 38 water table.

FC - KL G, GL, DYB Mors, Moders Imperfectly drained. May haveoften gleyed 5 - 12 - 17 compacted horizons at depth.

FLs - S G, R, DYB Moders Moderately well to imperfectly1 - 10 - 19 drained. Fluctuating water table.

FL G, (M) Moders Poorly drained. Consistently high18 - 41 - 80 water table. Poor aeration.

-- M, F, (G) peaty “O” horizons Permanently high water table. Poor> 60 cm aeration.

-- M, G peaty “O” horizons Non-forested fens/marshes. Too wet> 1 m and cold for tree growth.

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6 WILDLIFE HABITAT INTERPRETATIONS

Historically, mature and old-growth forests dominated the landscapes ofthe PRFR. On the coast, disturbance of these forests consisted of small-scale blowdowns, landslides, flooding, and the occasional fire. In theinterior, wildfires have shaped the forest landscape, burning large tractsof forest, but leaving a legacy of snags, veteran trees, and a mosaic ofunburned forest. The wildlife species found here have evolved to useattributes typical of these natural forest mosaics. The progressiveconversion of wild forests to managed plantations via conventional even-aged harvest practices will affect these species. The challenge is to applyour knowledge of natural disturbance regimes and wildlife habitatrequirements to harvesting and silvicultural practices so that we canmaintain important attributes of mature and old-growth forests inharvested stands.

We use the term “wildlife” to refer to all terrestrial vertebrates,including amphibians, reptiles, birds, and mammals. “Wildlife habitat”describes the components of the environment on which wildlife dependdirectly or indirectly for food, cover, and reproduction. Fundamentally,the health and diversity of wildlife populations are strongly tied to thequality and diversity of wildlife habitat. Therefore, in this chapter, wepresent approaches to maintaining wildlife through the conservation ofimportant wildlife habitats and habitat components.

The objective of this chapter is to give forestry practitioners a generalunderstanding of wildlife habitats and habitat components that shouldbe considered in harvest and silvicultural planning at both the standand landscape levels. In addition, wildlife habitats that are particularlysensitive to forestry practices are highlighted. This chapter is presentedin five main sections:

• a general discussion of wildlife diversity within the region;

• an outline of characteristic habitat features and selectedspecies of management concern for each biogeoclimaticzone/subzone;

• a description of key habitats, habitat components, and speciesof management concern;

• wildlife habitat considerations in harvesting and silvicultureplanning; and

• a summary of wildlife habitat considerations for PHSPs.

6 • 1

Information presented here has been compiled from several sourcesMeidinger and Pojar 1991; Radcliffe et al. 1993; Steventon 1993;Klenner 199110; Lloyd 199211; Madrone Consultants 199212). Specificreferences in the text are minimized. Appendix 1 contains an extensivelist of references relevant to the management of wildlife habitat in thePRFR.

6.1 Regional Wildlife DiversityThe PRFR includes a large variety of distinct landscapes that providehabitats for a diverse assemblage of wildlife species. In total, 333wildlife species are known to occur in the region: 262 birds, 62mammals, 7 amphibians, and 2 reptiles. This corresponds to 53% of theprovincial list of mammals, 65% of the birds, 35% of the amphibians,and 11% of the reptiles. Many arctic species find their southern limits inthe northern portion of the region and some southern species haveranges that just extend into the southern portion of the region.

Mammals that reach their northerly limits within the region include theSouthern Red-backed Vole, and several of the bats, such as Keen’sLongeared Myotis (which is largely confined to British Columbia) andthe Silver-haired Bat. The latter two species are restricted to coastalareas. Species that occur throughout much of the region and reach theirnorthern limit within the Yukon include the Deer Mouse, Heather Vole,Least Chipmunk, and Long-tailed Vole. Other mammal species typicallyfound throughout the region include Moose, Marten, Red Squirrel,Snowshoe Hare, Beaver, Porcupine, Short-tailed Weasel, Gray Wolf,Grizzly Bear, and Black Bear. Of international consequence, the regioncontains a significant proportion of the world’s Mountain Goat, andimportant populations of Grizzly Bear and Woodland Caribou.

Many northern birds have British Columbia breeding records only inthis northwest region of the province. These include the Oldsquaw,Wandering Tattler, Hudsonian Godwit, Red-necked Phalarope,Gyrfalcon, Northern Shrike, Common Redpoll, American Tree Sparrow,Snow Bunting, and Smith’s Longspur. Alpine and northern breedingspecies shared with other regions include the Rock Ptarmigan, WillowPtarmigan, Pine Grosbeak, and White-winged Crossbill, as well as threeowl species: the Boreal Owl, Great Gray Owl, and Northern Hawk Owl.As on other parts of the coast, Marbled Murrelets are common in someinlets, such as Gardner Canal and Khutzeymateen Inlet, and likely arebreeding in the old-growth forests found there.

10 Klenner, W. 1991. Pre-harvest silvicultural prescriptions to protect and maintainwildlife habitat. Unpubl. contract rep. B.C. Min. For., Vancouver, B.C.

11 Lloyd, R. 1992. Wildlife interpretations for the SBS, ESSF and ICH biogeoclimaticzones of the Prince Rupert Forest Region. Unpubl. contract rep. B.C. Min. For.,Smithers, B.C.

12 Madrone Consultants. 1992. Wildlife interpretations for the CWH biogeoclimaticzone of the Prince Rupert Forest Region. Unpubl. contract rep. B.C. Min. For.,Smithers, B.C.

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The Western and Common Garter Snake are the only two reptilesoccurring in the region, found specifically in low-elevation interior andcoastal zones. Of the seven amphibians found in the region, only four arefound in both interior and coastal forests: the Western Toad, Wood Frog,Spotted Frog, and Long-toed Salamander. An additional three, theTailed Frog, Rough-skinned Newt, and Northwestern Salamander, occuronly in coastal areas of the PRFR.

The PRFR also contains several species considered to be “at risk” underthe provincial wildlife strategy. These species are on the provincial redand blue lists, indicating that special management consideration isrequired because of declining or endangered populations.

The Red List contains species considered endangered or threatenedbecause of low abundance and the possibility of extirpation or extinction.Endangered species are any indigenous species threatened withimminent extirpation throughout all or a significant portion of theirrange in the province. Threatened species are any indigenous speciesthat are likely to become endangered in British Columbia if factorsaffecting their decline are not reversed. Two species found in the PRFR,the Keen’s Long-eared Myotis and Anatum Peregrine Falcon, arered-listed as provincially endangered species.

The Blue List consists of sensitive or vulnerable species that arepotentially at risk but not yet threatened. Population viability is aconcern, as indicated by a significant current or predicted downwardtrend in population numbers or density and habitat suitability.Forty-eight species are found on the provincial blue list. Included are theTailed Frog, Bald Eagle, Peale’s Peregrine Falcon, Gyrfalcon, Fisher,Grizzly Bear, Dall’s Thinhorn Sheep, Wolverine, and Caribou.

A complete list of wildlife occurrence by biogeoclimatic unit within thePRFR can be found in Radcliffe et al. (1993). Some areas of the region(such as the extreme northwest) and some groups of species (mostnotably amphibians and reptiles) have received limited sampling in thePRFR and our knowledge of these is mainly anecdotal.

6.2 Overview of Wildlife Species and Habitats for eachof the Biogeoclimatic Zones and Subzones

Each subzone in the region is typified by characteristic forest types andenvironmental features, which, to a large extent, define the habitatsavailable for wildlife. This section highlights some important wildlifespecies and habitats occurring in each of the PRFR zones, as well assome of the climatic restrictions affecting wildlife distribution.

6.2.1 Alpine Tundra Zone

Harsh climate and rugged topography are overwhelming factorsinfluencing the assemblage of species in the AT zone. Exposed rock andice, devoid of vegetation, are the most common features of the AT and

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6 • 3

provide little habitat for most wildlife species. However, alpinegrasslands, meadows, scrub, and krummholz interspersed with rockcliffs and talus slopes provide habitat for some species.

Although the AT has not yet been divided into subzones, three broadclimatic types can be recognized: the Coastal (above the MH zone), theInterior (above the ESSF zone), and the Northern (above the SWBzone).

Coastal alpine tundra is characterized by exceptionally high snowfalland extensive snowfields and glaciers. The snowpack does not melt awayuntil well into summer. Vegetation is sparse, consisting primarily ofmountain-heathers. Even Mountain Goat, which are well adapted towintering in the AT, generally descend to lower elevations along thecoast in winter months. Common species include the White-tailedPtarmigan, Rock Ptarmigan, Wolverine, and Hoary Marmot. Caribouand Thinhorn Sheep are absent from these coastal alpine areas.

Interior alpine areas are drier and generally support more species thando coastal alpine areas. Overwintering populations of Caribou andMountain Goat occur in areas where winds expose vegetation for winterforage. Mule Deer, Moose, Grizzly Bear, and Black Bear are found inkrummholz and alpine meadows during summer and fall months. Othercommon species are the Wolverine, Hoary Marmot, White-tailedPtarmigan, Rock Ptarmigan, Horned Lark, Water Pipit, and Rosy Finch.

The northern alpine tundra is the coldest and generally driest alpinetype. Extensive alpine plateaus are common and provide the favouredhabitat for Caribou. Thinhorn Sheep and Mountain Goat are commonthroughout the north where suitably rugged terrain occurs. Othercommon mammals include the Grizzly Bear, Gray Wolf, Red Fox,Wolverine, Hoary Marmot, and Arctic Ground Squirrel. Collared Pikaand Dall’s Sheep are found in the extreme northwest corner of theregion. Characteristic birds include Gyrfalcon, Golden Eagle,White-tailed Ptarmigan, Rock Ptarmigan, Horned Lark, Snow Bunting,Water Pipit, and Rosy Finch.

6.2.2 Boreal White and Black Spruce Zone

Species diversity in the northern BWBS zone is strongly affected by theharsh boreal climate; this is a major limitation for the distribution ofmany vertebrate species. Only those physiologically or behaviourallyadapted to survive the long, cold winters (e.g., through hibernation ormigration) can occur year-round. However, overall wildlife speciesdiversity is relatively high, particularly at the lower elevations: 256wildlife species occur in the BWBS, making it second only to the CWH.This is partly a reflection of a large number of arctic species withsouthern range limits that extend into the most northerly portion of theregion, as well as the large numbers of migratory bird species that usethese northern areas during the summer.

In the north, extensive brushfields of the SWB zone and open tundra ofalpine plateaus dominate. Boreal forest is often restricted to valleybottoms. These lower-elevation forests have the least snowfall of the

Wildlife

6• 4

northern zones and are consequently used by overwintering species toescape the deep snowpack and exposed conditions of the higher-elevationzones. Frequent fires have formed a mosaic of forests of different ages inthe BWBS. Conifers are often slow to re-establish after fire, anddeciduous forests of aspen, birch, and willow are common and persistent.These purely deciduous and mixed conifer-deciduous forests are veryproductive habitats for ungulates, birds (including many warblers,thrushes, vireos, and flycatchers), and a variety of small mammals.Moose, Caribou, Mule Deer, Gray Wolf, Black Bear, Lynx, Red Squirrel,Ermine, Snowshoe Hare, and Deer Mouse are common mammal speciesin the BWBS. Some bird species such as the Northern Goshawk, GreatHorned Owl, Ruffed Grouse, Common Raven, Gray Jay, DownyWoodpecker, and Black-capped Chickadee are common year-roundresidents, while Yellow-bellied Sapsucker, Hermit Thrush,Yellow-rumped Warbler, Purple Finch, and Dark-eyed Junco arecommonly found in these areas during the summer. Important breedinghabitat for many waterfowl species (particularly Northern Pintail,Scaup, and Green-winged Teal) is provided by extensive low-elevationwetlands in the BWBS.

6.2.3 Coastal Western Hemlock Zone

The CWH zone is relatively rich in wildlife species compared to interiorand northern areas because coastal climates are mild, forest productivityis higher, and the structural diversity in coastal old-growth forests isgreater than in interior old growth. Ecosystem diversity across thepredominantly forested landscape is also very high, with aninterspersion of numerous localized habitats such as bogs, talus slopes,rock outcrops, riparian areas, estuaries, avalanche tracks, and shorelinespray zones. Relatively mild winters enable a greater diversity of speciesto winter here than elsewhere in the region. The CWH providesimportant wintering habitat for species such as the Trumpeter Swan (inestuaries and lakes), Barrow’s Goldeneye, Harlequin Duck, and WesternGrebe (inshore waters). Many forest-dwelling species, including raptors,woodpeckers, game birds, and passerines, are resident all year. Themoist, mild climate permits several amphibian species, largely absentelsewhere in the region, to inhabit this zone.

The CWH provides important habitat for several species on theprovincial red and blue lists; these include the Keen’s Long-earedMyotis, Grizzly Bear, Sea Otter, Bald Eagle, Marbled Murrelet,Peregrine Falcon, and the Tailed Frog.

In the CWHvh2, the PRFR’s most maritime variant, bogs and bogwoodlands are extensive, with localized fens and marshes. Shore pine isoften a predominant feature, along with many snags and dead-toppedcedar trees. Dense salal understories are also common. Species that usethe seashore/forest interface thrive, exploiting rich marine feedingsources and secure forested nesting, denning, or alternative feedingsites. These include the River Otter, Mink, Black Bear, and Bald Eagle.

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6 • 5

The CWHvm has greater wildlife diversity than either thehypermaritime or submaritime CHU subzones. It supports considerablespecies diversity due to its proximity to the marine environment, andthe sheltered inlets are important wintering habitats for manywaterfowl. The CWHvm also includes numerous wetlands, avalanchetracks, estuaries, and extensive riparian corridors. This subzone has anabundance of excellent habitat for Grizzly Bear, particularly in thelower-elevation variant (CWHvm1) along such rivers as theKhutzeymateen, Kitlope, and tributaries to the Skeena. It is likely thatMountain Goat winter in this subzone at certain times. SmallBlack-tailed Deer populations occur in pockets, although the value fordeer is not high overall.

Records for the CWHwm subzone are limited, but it probably has thelowest wildlife diversity of the CWH subzones. Its northerly distributionand scarcity of estuaries reduce the number of species that find suitablehabitat here. Several wildlife species reach their northern limits in thissubzone (e.g., Keen’s Long-eared Myotis, Southern Red-backed Vole, andBlack-tailed Deer). However, this subzone does support some typicallynorthern or interior species that are absent from the other CWHsubzones, such as the Wood Frog and the Northern Red-backed Vole.Black and Grizzly Bear are abundant in the CWHwm.

The CWHws, the most interior subzone of the CWH, is less moderatedby the marine influence, and consequently the climate is more extremethan in other CWH subzones. A number of typically interior speciesoccur whose numbers gradually diminish toward the outer coast (e.g.,Moose, Striped Skunk, Clark’s Nutcracker, Black-backed Woodpecker,and Great Gray Owl). However, species that rely on the marineenvironment are not found, since this subzone includes no coastline.

6.2.4 Engelmann Spruce – Subalpine Fir and MountainHemlock Zones

The ESSF and MH zones range from high-elevation forestland tosubalpine parkland, characterized by short, cool summers and long, cold,snowy winters. Most wildlife species that inhabit these zones areadapted to survive or avoid the deep snow. Snowshoe Hare and Lynxhave large feet that enable them to run on top of snow, whereas Mooseand Mule Deer migrate to the valley bottoms during winter and springto avoid the snow. Similarly, Mountain Goat (MH and ESSF) andCaribou (ESSF only) use mature, closed-canopy subalpine forests toavoid the deep snow and storm conditions in the AT. The ESSF providesparticularly important summer foraging and winter denning areas forGrizzly Bear in the subalpine parkland. There are several bird speciescharacteristic of the higher-elevation forests, including the Clark’sNutcracker, Golden-crowned Sparrow, Hermit Thrush, and Willow andRock Ptarmigan. Mammals such as the Collared Pika, Wolverine,Mountain Goat, Hoary Marmot, and many other small rodents often findoptimal habitats in these high-elevation forests and parklands.

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6• 6

Avalanche tracks, rocky bluffs, caves, and talus slopes are importanthabitat features of the ESSF and MH. Forested land around thesefeatures may be particularly important for security and thermal cover.Small lakes provide breeding habitat for wetland species such asBarrow’s Goldeneye and Spotted Sandpiper. Riparian areas formimportant travel corridors both for the dispersal of young animals andfor migration between high-elevation and low-elevation seasonal ranges.Some excellent Grizzly Bear and Caribou habitats also occur,particularly in the ESSF. Many raptors find excellent huntingopportunities in these forests and adjacent parklands, and some useassociated cliffs and talus slopes for nesting habitat.

The ESSFwv is the northernmost ESSF subzone, occurring mainlyabove the ICH. It has the wettest growing season and the deepestsnowpack. Wildlife species that do not tolerate deep snow are either rareor absent here. The combination of deep snow and steep terrainproduces many avalanche tracks, which are important forage areas forGrizzly and Black Bear, Moose, and Mountain Goat. Forests adjacent tothese tracks are important for hiding and thermal cover for speciesusing avalanche tracks as forage sites. This subzone containsparticularly important winter habitat for Grizzly Bear, which use fairlysteep, forested, undisturbed sites for denning.

The ESSFmc is the driest of the ESSF subzones, with the lowest wintersnowpack. Because it occurs mostly on the highest elevations of theNechako Plateau, it is generally less steep, with fewer avalanche tracksthan other ESSF subzones. The lower snowpack allows ungulate use ofthese higher-elevation areas for longer periods. The mid-elevation slopesin the upper reaches of the Babine and Nilkitkwa rivers are importantdenning areas for Grizzly Bear. Caribou in the Telkwa and Tweedsmuirareas use the ESSFmc as summer and fall range, as migration routes,and sometimes as calving areas. The Telkwa herd may also use thissubzone to avoid periods when snow is wet or crusted in the herd’sprimarily alpine wintering areas.

The ESSFmk is the least diverse of the ESSF subzones, and its value tomost wildlife species may lie mainly in its relative wilderness character.Dry summers produce limited shrub and herb growth, and snowywinters limit use by ungulates. The southern portion of the subzone(Tahtsa Lake to Eutsuk Lake) is used by Caribou for summer and fallrange. Whitebark pine is common in this subzone and its seed is thefavoured food of the Clark’s Nutcracker.

The MHwh is the wettest, coastal subalpine subzone. The snowpack ofthis subzone can be deep and wet, but it disappears earlier than in lessmaritime subzones. Topography is rolling and for the most part lacksthe steep granite cliffs typical of the MHmm subzone. Because of highrainfall, forests are scrubby and sloping bogs are abundant. Wildlifediversity and use of these areas is low.

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The MHmm1 and MHmm2 usually have very deep and long-lastingsnowpacks. Unlike the MHwh, precipitous terrain means that much ofthe elevation range that would normally support MH forests is too sheerto support any forest at all. As a result of this severe terrain andclimate, species diversity is low. However, large populations of MountainGoat are found and Grizzly Bear frequent some areas during summermonths. Significant populations of the Tailed Frog may also be found inthese subzones.

For the most part, all of the subalpine subzones are likely to be used bymany of the vertebrates in adjacent, lower-elevation subzones (i.e., manyof the CWH species will occur in the MH, and many SBS and ICHspecies will occur in the ESSF).

6.2.5 Interior Cedar – Hemlock Zone

The ICH zone in the PRFR is transitional between coastal andcontinental climates. Forests can be highly productive, reflecting longand relatively moist growing seasons. The zone contains many interiorand coastal wildlife species. Species diversity is high in the southernportion of the zone, reflecting the relatively less severe winter andsummer climates, and also the presence of extensive seral forests.Northern ICH subzones have deep snowpacks that restrict manyspecies.

The ICHmc1 comprises the upper and middle sections of the NassBasin and is wetter and snowier than the ICHmc2, but not as extremeas the more northern ICHvc and ICHwc. Grizzly and Black Bear are ofparticular management concern in this subzone. A diversity of habitatsis the key to habitat quality for Grizzly Bear. The extensive wetlandcomplex in the Swan Lakes area is important to waterfowl such asBarrow’s Goldeneye, Bufflehead, Common Merganser, Common Loon,and wading birds.

The ICHmc2 is the driest of the ICH subzones and has the lowestsnowpack, making it an important wintering range for large populationsof ungulates. Extensive deciduous stands in this subzone provide springforage for many species and support concentrations of passerines thatrequire deciduous forest for nesting and foraging. Due to considerableagricultural and forestry development, this subzone is sensitive tofurther forest clearing, particularly in low-elevation valley bottoms.

The ICHvc and (to a lesser extent) the ICHwc are dominated by deepand long-lasting snowpacks. Species such as Fisher and Mule Deer thatdo not tolerate deep, wet snow, are absent or rare from these variants;other species, such as Moose, may use old-growth subalpine fir forests invalley bottoms or migrate to others areas to avoid the deep snowpack.

Black and Grizzly Bear are very important in the ICHvc and ICHwc; thearea of Hanna Creek and Tintina Creek is particularly productive forGrizzly Bear. Maintenance of berry-producing species, wetland herbs,and forest cover around salmon-producing streams is a priority.

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6.2.6 Sub-Boreal Pine – Spruce and Sub-Boreal SpruceZones

The interior sub-boreal forests have a relatively high diversity of wildlifefor the region. Although winters are long and harsh, many speciesoverwinter in the lower elevations of the SBS where snowpacks are lowand the spring flush of vegetation occurs early. Extensive deciduousforests in the lower-elevation valleys also support high populations ofmigratory passerines. The SBS and SBPS provide some of the besthabitat in the province for some species such as Moose, Marten, andFisher.

The SBPSmc subzone is drier and colder than the SBS subzones, andthe wildlife species that occur are adapted to survive or avoid the long,cold winters. Species diversity in this subzone is relatively low — on parwith the ESSF zone. Of particular concern in the SBPSmc are WoodlandCaribou that often winter in open, mature pine forests having abundantterrestrial lichens. Mature, moist spruce forests are less common thanpine-dominated forests, but are especially valuable for their arboreallichens, which provide winter forage for Caribou and Mule Deer. Theseforests also support relatively large trees that provide better,longer-lasting snags for cavity-dwellers. Wetlands are common in theSBPSmc, providing abundant waterfowl nesting habitat. Riparianshrubs and herbs provide forage and cover for many species, includingCaribou (in spring), Moose, Beaver, Muskrat, Common Yellowthroat,and Marsh Wren. The adjacent riparian forest provides cover, nesting,and denning sites.

The climate of the SBSdk is generally less harsh than that of theSBPSmc and SBSmc2 — conditions are milder and moister than in theSBPSmc and the snowpack is neither as deep nor as long lasting as inthe SBSmc. Wintering ungulates use the SBSdk extensively to avoiddeep snow of the adjacent SBSmc2 and ESSFmc subzones, especially inlate winter. Mature spruce forests intercept snow and are particularlyvaluable, as their arboreal lichens provide winter forage for Mule Deerand (in the south) Caribou. Repeated fire disturbance along the Bulkleyand Endako river valleys has resulted in many seral aspen stands thatenhance the value of this area for species such as Snowshoe Hare, Lynx,Moose, Mule Deer, and migrating passerine birds. Also, nativegrasslands and agricultural pastures provide a patchwork of openhabitats within these aspen forests that is favoured by some species(e.g., raptors, bluebirds, Coyote, and some rodents). This subzonecontains the most important Fisher habitat in the region. Lakes,streams, and wetlands are common; wetland and riparian shrubs andherbs provide forage and cover for many species, including Grizzly Bear,Moose, Beaver, Alder Flycatcher, and Yellow-headed Blackbird. Forestcover around salmon-producing streams is very important for GrizzlyBear.

As in the ICHmc2, agriculture, human settlement, and (to a lesserextent) forestry development have significantly reduced the area ofmature forest within the SBSdk. This increases the potentiallandscape-level impacts of further forestry activities on the remainingnatural stands.

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The SBSmc2 is wetter and snowier than the SBPSmc or the SBSdk.Species such as Mule Deer that do not tolerate deep snow are lesscommon in the SBSmc2 than in the SBSdk, and mature spruce andsubalpine fir forests are particularly important for thermal cover andsnow interception. In the SBSmc2, living trees and snags are generallylarger than in other sub-boreal forests and can provide nesting anddenning sites for many species. Also, dead and downed woody materialis larger and more abundant, which enhances habitat values for smallmammals and their predators, notably Marten. Lakes, streams, andwetlands are common. Riparian shrubs and herbs provide forage andcover for many species, while the adjacent forest provides cover, nesting,and denning sites. Forest cover around salmon rivers such as theBabine, Upper Morice, and Shelagyote is very important for GrizzlyBear.

6.2.7 Spruce – Willow – Birch Zone

The SWB has the harshest climate of all the forested zones in theregion. The climate has a profound effect on the wildlife species thatoccur here, an effect that is especially noticeable at the end of summerwhen oncoming winter triggers a migration by birds and mammals toareas more suitable for overwintering.

Moose and Caribou are widespread and abundant in this zone in thesummer, but typically are not present year-round, preferring instead tomigrate to lower elevations during the most severe winter conditions.Other mammals that use the SWB in the summer include Grizzly Bear,Black Bear, Thinhorn Sheep, Snowshoe Hare, Lynx, Wolverine, Marten,Red Squirrel, and Gray Wolf. Common bird species are Spruce Grouse,Common Raven, Gray Jay, Boreal Chickadee, Red-breasted Nuthatch,Three-toed Woodpecker, and Ruby-crowned Kinglet in the forestedlandscape, and Willow Ptarmigan, Gyrfalcon, and Wilson’s Warbler inthe shrub habitat that is abundant in this zone. Important breedinghabitat for Scaup, Green-winged Teal, Northern Pintail, Bufflehead,Arctic Tern, Red-necked Phalarope, and Red-throated Loon is found inthe wetlands and shallow lakes that dot the SWB landscape.

6.3 Habitats, Habitat Components, and Species ofManagement Concern

Wildlife habitat is “the air, soil, water, food, and cover components of theenvironment on which wildlife depend directly or indirectly in order tocarry out their life processes” (B.C. Wildlife Act 1982). Habitatmanagement for individual species is complex and often operationallyimpractical, except where a species is of special regional significance (e.g.,Caribou and Grizzly Bear). The approach promoted in this guide is tomanage for habitat diversity and the habitat features used by groups of

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species. Often, several species can be grouped together for managementpurposes, based on shared requirements for these habitat components(Table 6.1).

Habitat management must be considered at two levels: the stand leveland the landscape level. Stand-level management focuses on specifichabitat attributes, structure, and composition of the forest—componentsthat are used by wildlife for feeding, resting, breeding, and cover.Landscape-level management focuses on the distribution of differenthabitats over large areas. If management practices provide a range ofage classes (from early seral to old growth) and plant communities atthe landscape level, and provide some or all of the specific habitatcomponents at the stand level, then the habitat requirements of mostwildlife species will be maintained.

This section begins with a description of key habitats within thelandscape that hold particular importance for wildlife because of thespecial habitat attributes they contain, or because they are rare orinfrequent. Important habitat components at the stand level are thendescribed. Finally, some specific habitat requirements of species groupsand selected species of management concern are presented.

6.3.1 Key habitats (landscape-level components)

Riparian areas are areas adjacent to, and influenced by, rivers,streams, lakes, and wetlands. They have characteristic vegetationcommunities and stand structures that differ from neighbouring uplandforests. They are extremely important for wildlife and are relatively rarefrom a landscape perspective.

Riparian forests have several characteristic features that contribute totheir ecological importance:

• lush understories providing cover and forage;

• high horizontal and vertical structural diversity providingabundant niche spaces for wildlife;

• moderate and stable microclimate;

• proximity to stream invertebrate and fish populations that areimportant food sources for many bird and mammal species; and

• access corridors to water sources and dispersal corridors toother areas.

Riparian areas range from narrow bands around wetlands and lakes andalong mountain streams to unconstrained floodplains on valley bottoms.These latter areas are particularly productive. Many wildlife speciesreach their highest densities in riparian habitats along low-gradientstreams, especially those adjacent to old-growth forests.

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TABLE 6.1. Selected species management groups

Species management group Associated speciesa

Primary cavity nestersb Black-capped Chickadee, Boreal Chickadee, Downy Woodpecker,Hairy Woodpecker, Mountain Chickadee, Northern Flicker,Pileated Woodpecker, Red-breasted Nuthatch, Red-breastedSapsucker.

Secondary cavity nestersb American Kestrel, Barred Owl, Barrow’s Goldeneye, BrownCreeper, Bufflehead, Common Goldeneye, Common Merganser,Great Gray Owl, Hooded Merganser, Merlin, Northern FlyingSquirrel, Northern Saw-whet Owl, Porcupine, Red Squirrel,Tree Swallow, Vaux’s Swift, Violet Green Swallow, WesternScreech Owl, Winter Wren, Wood Duck.

Snag users Bald Eagle, Belted Kingfisher, Big Brown Bat, Black Bear,Bushy tailed Woodrat, California Myotis, Deer Mouse, DuskyFlycatcher, Ermine, Fisher, Great Horned Owl, Keen’sLong-eared Myotis, Marten, Mink, Northern Goshawk,Olive-sided Flycatcher, Porcupine, Silver-haired Bat, YumaMyotis.

Coarse woody debris users Black Bear, Bushy-tailed Woodrat, Common Shrew, Deer Mouse,Dusky Shrew, Ermine, Fisher, Heather Vole, Long-tailed Vole,Long-toed Salamander, Lynx, Marten, Mink, NorthwesternSalamander, Porcupine, Ruffed Grouse, Red Squirrel,Red-backed Vole, Townsend’s Solitaire, Vagrant Shrew, WinterWren, Wolverine.

Large tree users Bald Eagle, Brown Creeper, Great Blue Heron, Great GrayOwl, Great Horned Owl, Marbled Murrelet, NorthernGoshawk, Osprey, Peale’s Peregrine Falcon, Porcupine, RedSquirrel.

Deciduous tree/ thicket users American Redstart, Beaver, Black-capped Chickadee, Bushtit,Cedar Waxwing, Chipping Sparrow, Common Redpoll, GreatHorned Owl, Long-tailed Vole, Moose, Mule Deer, NorthernHawk Owl, Pileated Woodpecker, Porcupine, Red-eyed Vireo,Ruby-crowned Kinglet, Ruffed Grouse, Snowshoe Hare,Swainson’s Thrush, Western Screech Owl, Western Wood-peewee,White-crowned Sparrow, Yellow Warbler, Red-breasted Sapsucker.

Riparian area users Bald Eagle, Barrow’s Goldeneye, bats (forest-dwelling),Beaver, Black Bear, Bufflehead, Common Merganser, DuskyShrew, Fisher, Great Blue Heron, Grizzly Bear, HoodedMerganser, Marbled Murrelet, Mink, Moose, NorthwesternSalamander, River Otter, Rough-skinned Newt, Tailed Frog,Vaux’s Swift, Wood Duck.

a Bolded species are selected species of management concern featured in Table 6.2, whichhas more detailed habitat information.

b Primary cavity nesters can excavate nests; secondary cavity nesters must rely on unoccupiednest holes created by primary cavity nesters.

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As a general rule, maintaining 70% of the structural components inriparian ecosystems will allow them to remain functionally intact.Logging activities in riparian areas should closely follow the Fisheries,Forestry, and Wildlife Guidelines developed for coastal and interiorforests, with maintenance of habitat as the primary objective.

Old growth refers to a forest with a complex of live and dead trees ofdifferent species in various sizes and age classes that are part of aslowly changing but dynamic ecosystem. The age and structure of anold-growth forest varies significantly by site unit and biogeoclimaticunit. However, old growth is typically distinguished from younger standsby several of the following structural attributes:

• presence of relatively large trees for the species and site;

• a wide variation in tree sizes and spacing;

• accumulations of large, dead, standing (snags) and fallen trees;

• a multi-layered canopy;

• canopy gaps and understory patchiness; and

• many trees with broken, deformed, and decayed tops or boles,and root decay.

Old-growth forests play a major ecological role in contributing tobiodiversity. In comparison to other seral stages, old-growth forests tendto have the greatest number of species with specialized habitatrequirements (although often not the greatest total number of species).Habitat characteristics of these older, senescing forests are difficult torecreate through management and these habitats are decreasing inextent due to harvesting. This has led resource planners to placeold-growth forests as the primary focus of a provincial biodiversitystrategy aimed at maintaining the ecological integrity of BritishColumbia’s lands. In general, coastal (CWH) and interior transitional(ICH) old-growth forests are more extensive and complex than ininterior landscapes (BWBS, SBS, and SBPS) where periodic firedisturbance reduces the extent of older forests.

At a landscape level, old-growth forests intercept snow in winter,providing areas with improved travelling efficiency and access to food, aswell as provide hiding cover. At a stand level, old growth has structuraldiversity that does not occur in younger forests and enables manyspecies to co-exist in the same habitat.

Shrub/herb communities are important habitats for many wildlifespecies. In general, these early seral plant communities produce moreforage and greater vegetation diversity than any other stage of forestdevelopment. Some shrub/herb communities, such as wetlands, drygrasslands, avalanche tracks, and subalpine brush, persist indefinitely dueto climate, edaphic factors, or frequent disturbance. Most, however, areshort-term (<20 years) stages arising from disturbance and are succeeded

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by deciduous and coniferous forest. In plantation forestry, managementobjectives are generally aimed at shortening the normal duration of thisseral stage in favour of closed-canopy coniferous pole-sapling stages.

Shrub/herb communities are most important to wildlife for browse andforage. Some bird species and small mammal species prefer shrub/herbcommunities for nesting and cover.

Wetlands are of critical importance to waterfowl, amphibians, andaquatic mammals. Marshes are the most productive type of wetland.Forests surrounding marshes are important for cavity-nesting duckssuch if Goldeneye, Wood Duck, Common Merganser, and Bufflehead.Other cavity nesters (e.g., bats), particularly those that feed on flyinginsects, also use wetland fringe forests. Fens are less productive wetlandecosystems that are often dominated by willow species, which are usedextensively as winter browse by Moose in areas with low snow depths.Fens often have high rodent populations, providing abundant prey forcarnivores. Bogs are the least productive type of wetland and the leastvaluable overall to wildlife, although they often support a variety ofinsectivorous birds.

Deciduous forests, composed of trembling aspen, paper birch, blackcottonwood, willows, and/or red alder, are used preferentially by manyspecies. In particular, many passerine birds use these forests for nestingand feeding. Deciduous forests are a mid seral stage establishedfollowing fire, flooding, or clearing. Agricultural land clearing, humansettlement, and forestry activities have decreased the total area ofdeciduous forests in the interior zones of the PRFR; wildfire suppressionand rehabilitation of burnt-over areas is also contributing to this decline,as existing deciduous forests give way, through natural succession orsilvicultural treatment, to mixedwood and coniferous stands.

Shoreline forests and estuaries are used by many wildlife speciesthat forage in the ocean. Old-growth shoreline forests provide nestinghabitat for the Bald Eagle, threatened Marbled Murrelet, and otherseabirds. Birds such as the Bald Eagle, Peregrine Falcon, Great BlueHeron, and Belted Kingfisher use shoreline trees for roosting andperching. Where freshwater streams and rivers enter the ocean, largedeltas, saltmarshes, and estuaries are formed, providing highlyproductive and important habitat for Grizzly and Black Bears, seabirds,ducks, and shorebirds.

South aspects are warmer and tend to have lower snow accumulations,which can favour species such as Mule Deer that do not tolerate deepsnow. They are also among the first sites to provide spring forage forother ungulates, bears, and other wildlife species.

6.3.2 Important habitat components (stand-levelcomponents)

Habitat components can be managed for at the stand level. Thestructural components of forests that receive significant use by manywildlife species in all forested landscapes are described.

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Snags and dying trees are particularly important for cavity dwellerssuch as woodpeckers, chickadees, some owls, and mammals such asMarten, Fisher, Northern Flying Squirrel, and even Black Bear. Inriparian areas, snags have particularly high value for bats (many ofwhich forage over the open water) and cavity-nesting ducks. Snags alsoprovide perches for birds of prey and insectivorous birds (e.g., swallowsand flycatchers) important in controlling potential forest pests.Generally, larger snags receive more wildlife use. Conventionallymanaged stands are generally too young, even at rotation age, to havedeveloped adequate sizes and abundance of snags.

Coarse woody debris (CWD), which includes sound and rotting logsand stumps, provides feeding substrate for a diversity and abundance ofinvertebrates and fungi. These in turn provide food for many mammals,birds, snakes, and amphibians. CWD is used as nesting and denningsites by many birds and mammals, as sheltered microhabitat by reptilesand amphibians, and even as courtship sites by some species (e.g.,Ruffed Grouse). Many small animals use CWD for security cover and foraccess below the snow (e.g., Marten and other weasels). As with snags,larger-diameter downed logs generally receive greater wildlife use.

Deciduous trees in a largely coniferous landscape provide habitatdiversity that is exploited by many wildlife species. Many songbirds(such as warblers, vireos, and flycatchers) preferentially use deciduoustrees as foraging and nesting areas. Many primary cavity nesters preferdeciduous species to conifers, possibly because cavity excavation iseasier. Aspen and cottonwood are particularly important because maturetrees frequently have heart rot. The smaller deciduous trees in riparianand adjacent areas are a required component for Beaver, a keystonespecies that creates valuable habitat for many other wildlife species.

Large veteran trees are important sources for future snags and CWDin forests. Because veteran trees are frequently in the early stages ofdecay, they are often preferred by cavity nesters and birds that foragefor insects found under the bark. Raptors often use veteran trees forperching and nesting.

Edges between vegetation communities (such as between mature timberand clearcuts, or between wetlands and mesic forest) are often used byspecies that use each area for different aspects of their existence. Edgesalso provide habitat for species that prefer the often structurallycomplex transition zone (ecotone) between contrasting ecosystems. It isimportant to recognize, however, that excessive edge, created as a resultof extensive patch clearing and habitat fragmentation, leads to a loss ofhabitat for species that require larger tracts of uninterrupted forest.

Forest canopy gaps increase the vertical and horizontal diversity of theforest, leading to greater wildlife diversity. They occur naturally where atree or group of trees falls over or dies standing, permitting sunlight toreach the forest floor and promote the growth of herbs and shrubs. Smallopenings add greatly to the structural diversity of the forest, particularly inareas of homogeneous closed-canopy forest (such as managed forests). Gaps

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provide forage and hunting opportunities for many species. In thewinter, these gaps, with surrounding forest that can provide snowinterception and cover, are used extensively by ungulates.

6.3.3 Species groups and selected species ofmanagement concern

Although all species in the ecosystem are components of biodiversity,some may be more important to managers than others because they:

• are rare or endangered;

• may create habitat for others (e.g., primary cavity nesters);

• require specific habitats that are adversely affected by land usepractices;

• are commercially valuable and hence a high population level isdesired; or

• are important silvicultural allies or pests.

Table 6.2 presents selected wildlife species found in the PRFR that fitone or more of these criteria.

Many of these species share similar habitat requirements and can thusbe grouped into species management groups (see Table 6.1).Management activities that maintain specific habitat components will bepotentially beneficial to all species that rely on that component. In caseswhere the effects of a management prescription on wildlife are beingmonitored, studying the response of one of the species in the group(known as a management indicator species) will give some indication ofhow the practices are affecting other species in the group.

6.4 Wildlife Habitat Considerations in TimberHarvesting and Silvicultural Planning

This section is a compilation of guidelines laid out in several draftdocuments dealing with forestry management for wildlife habitat andbiodiversity. Field workers who require more detailed and specificguidelines for landscape and stand structure objectives should consultthese papers. Documents available or in preparation include:

• Fish, forestry, and wildlife guidelines for coastal forests (B.C.Coastal Fisheries/Forestry Guidelines Technical Committee1992) and interior forests (B.C. Interior Fish, Forestry, andWildlife Guidelines Committee 1993)

• Guidelines to maintain biodiversity in coastal forests (B.C.Ministry of Forests/B.C. Ministry of Environment 1992) andinterior forests (Steventon 1993)

• Provincial harvesting guidelines for the management andmaintenance of wildlife trees (Wildlife Tree Committee of B.C.1993)

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TABLE 6.2. Habitat features of selected species of management concern

Species Habitat Features

AMPHIBIANSNorthwestern Associated with mature and old-growth forest. CWD probably important. Feed inSalamander the forest near still water; generally at lower elevations. Need permanent water for

reproduction. Coastal areas only.

Tailed Frog Associated with forested (often coniferous old growth) riparian areas along fast-moving streams in the CWHvm and CWHws. A blue-listed species.

BIRDSBald Eagle High densities near coast. Associated with old growth, particularly with large

trees to support heavy nests. Nest in riparian and shoreline forests, near feeding habitats. Scavenge and hunt along shorelines, estuaries, salmon rivers. Blue-listed.

Barrow’s PRFR contains majority of breeding range. Nest in large tree cavities in wetlandGoldeneye riparian areas. Overwinter in protected coastal inlets. Secondary cavity nester.

Brown Creeper Abundant in old-growth forests, which may be optimal habitat. Uses older trees with thick, furrowed bark.

Marbled Murrelet May depend on coastal old growth for nesting habitat; large, mossy limbs ofconifers used. Common along the mainland coast, and a significant portion of the world population probably breeding here.

Northern In many habitats in winter, but otherwise generally in coniferous or mixed forests. Goshawk Nest in 150 + yr conifer stands, northerly exposures.

Peale’s Peregrine Coastal. Hunt for birds (e.g., Ancient Murrelets) in marine and wetland habitats. Falcon Generally cliff nesters, but some nest in large trees.

Pileated Region-wide resident of mature coniferous and mixed forests. Use coniferous andWoodpecker deciduous trees for nest cavities. Generally need trees at least 25 cm dbh

(preferably > 50 cm dbh) for nesting. Use CWD, snags, live trees for foraging.

Vaux’s Swift Nest and roost in tree cavities or broken tops. Possibly dependent on old-growth forests. Forage over openings, riparian areas, and wetlands.

MAMMALSBeaver Use riparian deciduous forests and willow shrublands. Highest densities in low-

gradient streams and sheltered lakes with plenty of deciduous trees <10 cm dbh.

Black Bear Adequate winter den sites extremely important. On coast, typically den in large cedar trees and CWD. Spring forage in wetlands, estuaries, riparian areas, or athigher elevations on southerly aspects. Summer forage often available in early seral plant communities, including burns, cutblocks, and wetlands. Berry crops and salmon streams highly significant in fall.

Caribou Potentially sensitive to human disturbance of forested migration routes and over-wintering areas. Summer in alpine and subalpine areas; winter in alpine areas andmature, lower-elevation, dry forests with high ground cover of lichens. A blue-listed species with limited distribution.

Fisher Secondary cavity nester in large cottonwoods. Summer use of riparian areas, pole-sapling forests, and mixed forest. Intolerant of deep snowpacks; winter activityprimarily in mature stands with dense canopy closure. Blue-listed species; indecline in recent years.

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TABLE 6.2. (Continued)

Species Habitat Features

Grizzly Bear Generally den at mid elevations. Spring forage habitats are estuaries sedge fens,avalanche chutes, and riparian areas/seepage sites. Carrion can also be important.Early seral vegetation provides some forage, particularly berry crops. Use oldgrowth for feeding and bedding in coastal floodplains. Riparian areas alongsalmon rivers extremely important, especially in fall. A blue-listed species.

Keen’s Long- Probably dependent on coastal old-growth forests with associated cliffs to roosteared Myotis and breed. Forage over ponds, riparian areas, etc.; 90% of the world population

believed to be in B.C. A red-listed species.

Lynx Depend on snowshoe hare. Use CWD in older stands for denning.

Marten Closely associated with mature forests, particularly more productive stands. Needunderstory diversity and plenty of snags, brush piles, and CWD to den and toprovide prey habitat, foraging cover, and hunting access below snow.

Moose Closely associated with, and may be dependent in severe winters on, maturedeciduous and mixed forests for feeding and shelter. Use wetland/riparian areaswith dense deciduous cover in summer, also shrubby avalanche tracks. Requireabundant browse; willow and red-osier dogwood important.

Mountain Goat Habitats generally very rugged. At high elevations in summer, generally abovetreeline. In winter, closely associated with mature forest canopy interspersed withcliffs and ledges (good escape terrain) for shelter, predator protection, and food.May occur at low elevations along the coast.

Mule/Black-tailed Use coniferous forests and open areas, burns, cutblocks, etc. In spring, use southDeer aspects, floodplains, wetlands, and young seral stages. In summer, young seral

stages are often used. In winter, use older forests with arboreal lichens andunderstory shrubs; warm aspects preferred.

Northern Flying Secondary cavity nester in mature conifer and mixed habitats. InteriorSquirrel populations primarily conifer seed eaters; coastal populations fungivores. Nests in

cavities and witch’s brooms. Important prey species for owls.

Porcupine Inhabit many forest types. Pole-sized conifers provide important winter food; maycause extensive damage in second-growth stands. Den in caves, rock crevices,and hollow trees. Larger-limbed trees are used for resting; brush piles are used forcover. Often in riparian habitats in spring and summer.

Red Squirrel Spruce trees often preferred. Use secondary cavities in large-diameter trees andwitch’s brooms for nesting. Populations may fluctuate with cone crops; coniferseeds are main food item. Use CWD for food caches.

Red-backed Vole, Very important prey species for most predators in the region. Prefers forestedNorthern and habitats with plenty of decaying logs and moss. Also in brushy habitats or inSouthern clearings under brush piles. Require lots of CWD on forest floor for cover.

River Otter Use coastal and riparian mature and old-growth forest for denning, often underlarge upturned trees. Also found under large tree roots, rock crevices, and inbeaver burrows. Need dense riparian cover. Log jams and riparian CWD provideimportant prey habitat, foraging cover, and den sites.

Snowshoe Hare Prefer brushfields or deciduous/mixed forests with willow understory.Populations follow a 7- to 10-year cycle. Important prey species.

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• Guidelines for maintaining biodiversity during juvenile spacing(B.C. Ministry of Forests/ Ministry of Environment 1993)

• Guidelines for integrating coastal Grizzly Bear habitat(Hamilton et al., in prep.)

• Pre-Harvest Silvicultural Prescriptions to protect and maintainwildlife habitat (Klenner 199113)

Full references for these and other wildlife references can be found inAppendix 1.

6.4.1 General guidelines for maintaining wildlife habitatvalues

Current forest management practices aim to establish viable coniferplantations as quickly as possible to achieve an 80- to 100-year rotation.Emphasis over the rotation is on coniferous pole-sapling and youngmature seral stages — stages that are generally of least value to wildlifeand have the lowest species diversity. These younger forests lack thestructural complexity that supports healthy populations of some wildlifespecies. The important stand habitat components, as describedpreviously, generally arise from senescing mature stands (old growth) orfrom complex younger stands that contain a significant component ofdeciduous tree and shrub species as well as scattered snags and veterantrees. Many of these characteristics are affected by forestry activities(Table 6.3).

In general, the two seral stages of the most value to wildlife are theinitial shrub-herb and old-growth stages. Preliminary recommendationsfor the ratio of early seral to mature stages in the landscape arepresented in Table 6.4.

Appropriate harvesting activities at the stand level can maintain someof the structural components typical of older forests. Preliminaryguidelines for preservation of structural components on zonal sites areoutlined in Table 6.5 and are based on surveys of natural matureforests. These values represent the minimum density of componentsbelieved necessary to maintain viable populations of attribute-dependentspecies in managed stands, and are meant to serve as target objectivesacross small- to medium-sized areas (10 - 100 ha). Note that the listeddensities are what should be present at the time of second-growthmaturity. Actual numbers must be higher at harvesting to compensatefor loss of attributes over the rotation. Natural stands show a highdegree of variability in distribution of snags and dead trees. Therefore,for the greatest wildlife use potential, there is value in clumpingretained trees.

The following two sections describe approaches to maintaining orenhancing important habitat components during harvesting andsilvicultural operations.

13 Ibid., p. 6•2.

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TABLE 6.3. Potential impacts of broad management activities onimportant stand structure attributesa

Structural Attribute

Large Coarse TreeManagement Activity green woody species Under- Stand

Snags trees debris diversity story structure

Silvicultural system * * * * * * * * **

Site preparation *b *b ** **

Regeneration *b *b ** * **

Vegetation * ** ** **management

Spacing and thinning **b * * ** ** **

Pruning *

Pest management ** ** * * * **

** potentially high impacts * potentially significant impacts.

a Adapted from Steventon (1993).b Activity does not necessarily affect attribute; however, safety regulations associated

with work site activities often require removal of wildlife trees that pose a potentialhazard to workers.

TABLE 6.4. Preliminary seral stage objectives by biogeoclimatic zone(percentages of 10 000- to 90 000-ha management units)a

Seral Stage ESSF/MH SBS/SBPS/BWBS CWH/ICH

Early to mid seral < 30% 5 - 50% < 30%

Matureb > 50% > 30% > 40%

Harvest unit sizec 0 - 100 ha 0 - 200 ha 0 - 100 ha

a Adapted from Steventon (1993).b “Mature” is used here to connote the presence of important structural attributes

typical of natural mature forests, such as large trees and snags. Approximateminimum years to achieve “mature” status in appropriately managed forests for theabove zone groups is 80 - 120 years, 60 - 80 years, and 40 - 80 years respectively.Clearcut stands with no retained snags or green trees will require at least doublethese times to begin to produce mature forest structural attributes.

c Generally, there should be a greater frequency of smaller rather than larger units,averaging approximately 40 ha. However, in specific situations a few large blocksmay be preferable over many small blocks (e.g., for the management of wintercaribou habitat in the SBPS). 0-ha harvest units are uneven-aged managed stands.Larger units may be composed of a “cluster” of smaller blocks.

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TABLE 6.5. Preliminary minimum structural objectives to bemaintained for mature a second-growth stands on zonalsitesb

SBSdk/Attributec SBSmc SBPS ESSF ICH CWH MHd

Snags/ha 9 6 10 5 5 5>17.5 cm dbh (99) (67) (121) (53) (23)

Snags/ha 3 3 8 2 2 3>27.5 cm dbh (24) (12) (84) (13) (11)

Snags/ha 2 1 4 3 3 2>37.5 cm dbh (11) (2) (40) (25) (13)

Total snags/ha 14 10 22 10 10 10(134) (81) (245) (91) (47)

CWD m3/ha 50 25 50 50 50 50>10 cm diam. (100) (100)

Stems/ha 400 400 400 400 300 400>17.5 cm dbh (798) (805) (887) (689) (337)

Large trees/ha 15 10 15 20 30 15>37.5 cm dbh (83) (37) (145) (175) (144)

a “Mature” as defined in Table 6.4.b Values outside brackets are minimum target densities to be present at second-growth

stand maturation; values inside brackets are average attribute densities for naturalzonal forests (based on surveys of > 35 stands from each zone).

c Snags and CWD should represent a range of decay stages from hard to soft.d No stands sampled.

6.4.2 Harvesting considerations

The following guidelines apply mostly to even-aged silvicultural systemsrather than uneven-aged systems. Uneven-aged silvicultural systems suchas single tree or group selection offer some advantages over clearcut systemsfor meeting wildlife habitat objectives because they maintain within-standstructural diversity. Assuming that all snags and large trees have not beenselectively removed, these sites will act very much like “mature” standswithin the landscape. Conversely, clearcutting promotes early seral (pole-sapling) stages and removes mature forest habitat components.Clearcutting may have some similarities to wildfire as a disturbance agent;however, it conspicuously lacks the structural “legacies” (patches of livetrees, veteran snags, and CWD) that typically remain after wildfire.Even-aged harvesting practices can be modified to maintain some ofthese habitat components in the managed forest through green tree/snag

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retention and manipulation of block size and shape. An overview of theeffects of management activities on important structural attributes ispresented in Table 6.3.

Green tree and/or snag retention

Patches of trees and snags within a cutblock provide immediate nestinghabitat and cover for some species (e.g., Tree Swallows, flycatchers, andbats). More importantly, they provide a source of large-diameter snagsfor the future forest. Seed tree or shelterwood systems retain greentrees, but some must be left unharvested to provide large-diametersnags during the next rotation (Table 6.5). In clearcuts, retainingpatches is usually safer and operationally easier than retaining singletrees and snags. Possible sites where groups of trees can be retained are:

• on areas of difficult or uneconomical harvesting such asin gullies, on unstable slopes, along intermittent streams, andaround rocky outcrops;

• along the boundary of the cutblock;

• on drier upland areas where such trees can also serve asshelterwood trees;

• on wet sites where trees are small or of poor quality, or wherelogging operations may lead to site degradation. Largehardwoods (aspen, birch, cottonwood) can be retained whereverpossible since they grow rapidly and should become usablesnags;

• in riparian areas where fisheries habitat guidelines restrictcutting practices. Live trees should be retained in addition tothe recommended fisheries streamside zone to develop as widea corridor of forested habitat as is feasible. Use of directionalfalling, faller selection, and yarding away from the area tocreate a buffer zone with a gradient of decreasing tree densityinto the clearcut is the optimal approach; and

• in uniform cutblocks where small groups of merchantabletrees may have to be considered for retention.

For safety reasons, snags should be maintained in patches (e.g., greentree retention areas, along riparian corridors) and should include bothhard (recently dead or dying, little decay) and soft snags (advanceddecay of firm trees with extensive heart rot) to maintain viablepopulations over time. Good candidates for large-diameter live trees thatcan be retained to become future snags are:

• trees with deformities, broken tops, or heart rot, whichreduce their economic value;

• large veteran trees; and

• hardwoods such as trembling aspen, paper birch, blackcottonwood, and red alder.

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Only windfirm trees that will continue to grow to at least 25 cm dbhshould be chosen.

CWT retention

Coarse woody debris is most effective as wildlife habitat when it is welldispersed over the cutblock or grouped in small units; large piles of logsprovide minimal habitat. Unmerchantable trees should be left wherethey fall.

Block size and shape

Small, dispersed harvest blocks (1 - 10 ha) provide a large amount ofedge habitat, which benefits many species. At a low level of harvest,small clearcuts do not fragment the landscape. However, at high levelsof forest removal, dispersed small clearcuts lead to excessive habitatfragmentation and this is deleterious to species that requireuninterrupted areas of early seral or mature forested habitat. Largerclearcuts (> 20 ha) have less edge habitat and, in early seral stages(shrub-herb and pole-sapling), may be favoured by species such as volesand Snowshoe Hare that can do considerable damage to plantations insome areas.

At present, it is unclear what landscape patterns are optimal tomaintain healthy populations of all species in different zones across theregion. However, it is clear that imposing a “checkerboard” of repetitivecutblocks of similar size and shape is not the best approach foroptimizing wildlife habitat. Varying the size, shape, and distribution ofclearcuts in the landscape is likely to be the most beneficial approach.Some points to consider are:

• Long narrow cutblocks can remove large volumes of timberwhile maximizing edge. It has also been proposed that longnarrow parallel cutblocks should be used in caribou migrationareas to reduce impacts.

• Small clearcuts of less than 10 ha maximize edge habitatand, in low densities, may act as natural gaps in the landscape.At higher rates of cut, clustered cutblocks are preferablebecause well-dispersed cutblocks may lead to excessivelandscape fragmentation.

• Clustered cutting patterns reduce the effects of landscapefragmentation and most closely resemble natural disturbancepatterns.

• Partial cutting maintains more of the habitat components inharvested areas than does clearcutting. Cutblocks that stillhave understory cover and patches of trees will providehabitats similar to those found in natural forests.

• Irregular block boundaries increase the amount of edge andthe diversity of edges in a cutblock.

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6.4.3 Stand management considerations

Wildlife habitat management objectives can be incorporated into forestmanagement planning during all phases. In general, the decisions madeearly on are the most critical for long-term habitat conservation.

Site preparation and reforestation

Site preparation has important consequences for short- and long-termwildlife habitat. Treatments such as prescribed burning or mechanicalsite preparation achieve desired reforestation goals by shortening thetime needed for conifers to become established. However, thesetreatments often remove, albeit temporarily, competing herb and shrubspecies and accelerate plant succession toward the pole-sapling stage.These plant species often provide important wildlife habitat.

Site preparation treatments also remove or rearrange both solid logsand decaying material on a site after logging. Large-diameter CWDprovides good foraging habitat, decays more slowly, and presents less ofa fire hazard than does smaller slash. Therefore, broadcast burningshould be prescribed such that only fine debris is removed. A moderate-or high-intensity burn will char and case-harden CWD, reducing itsvalue for wildlife. Low-intensity burns will maintain valuable CWDwhile removing fine slash and may also increase plant species diversityand wild fruit and forage production.

Mechanical site preparation treatments that remove CWD or aggregateslash excessively should be avoided, since they reduce the habitatavailable to the CWD users. Site preparation treatments that pile slashcreate clusters of prime habitat for potential pest species such as voles.

The selection of tree species for reforestation will have a long-term effecton stand structure. Blocks planted with several species will providediverse habitats compared to a monoculture. Planting should bedesigned to create a mixture of conifer and hardwood species ecologicallysuited to the site. Hardwoods should be retained wherever possible tomaintain habitat diversity.

Vegetation management

Vegetation management treatments aimed at controlling competingbrush should be applied with discretion. Competing brush provides coverand forage for many wildlife species. If brush control is necessary forconifers to attain free growing status, patches of brush should beretained:

• along creeks and streams;

• in areas of low forest productivity (e.g., rock outcrops, wet soils);

• in green tree/snag retention areas;

• where severe brush problems are not anticipated; and

• in areas of high forage use by wildlife.

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Prescriptions should be considered that reduce the area requiringbrushing, such as treating areas only in the immediate vicinity of croptrees. Cluster planting of about five seedlings per cluster with reducedstocking should be considered so that vegetation managementtreatments can be intensively applied around the tree clusters, ratherthan broadcasting treatments over the entire block. On problem sites,fast-growing hardwoods (e.g., black cottonwood) may be better able tocompete with brush than conifers. Rather than attempting to controlbrush in these areas in order to establish conifers, it may be preferableto plant hardwoods. Some brushy areas, such as those dominated byred-osier dogwood, willows, and berry-producing shrubs, provideespecially important wildlife foraging habitat and should be noted insilvicultural plans for special management consideration.

Stand tending

Spacing and commercial thinning can be used to increase verticalcanopy diversity and the quantity of understory forage in even-agedstands. Thinning treatments that remove groups of trees simulatenatural gaps (see Section 6.3.2) and promote shrub and herbdevelopment. Tree removal by girdling or hack-and-squirt herbicideapplication can also increase understory growth and provide snags. Onthe other hand, low thinning, dominant thinning, and selective removalof deciduous trees diminishes stand structure. Wildlife habitatattributes can be promoted in thinning treatments if the followinggeneral guidelines are followed:

• Retain all safe snags and veteran trees, as well as some large,mature green trees.

• Vary stand density within a treatment area by leaving somepatches unthinned and increasing the spacing in others.

• Maintain a mixture of tree species within the stand.

• Keep obvious wildlife trails free of slash.

Pest management

Pest management treatments in mature forests (e.g., pine beetle androot rot control) can have a significant impact on stand structure. Thesepest episodes are natural processes that, in wild forests, create snagsand forest gaps. Treatments such as fell-and-burn selectively removefrom the forest dead and dying trees that are used extensively by cavitynesters. Indiscriminant application of these treatments should beavoided.

6.5 Summary of Wildlife Habitat Considerations inPre-Harvest Silvicultural Prescriptions

The approach we have taken in this chapter is to provide forestry fieldworkers with a basic understanding of important wildlife habitats andhabitat components so that wildlife concerns can be addressed in day-to-day forestry activities. Integrating wildlife habitat objectives and forest

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management at the stand level begins with the PHSP. To summarizethe information presented in this chapter, a checklist of habitat valuesthat should be considered during the development of a PHSP isprovided. Points are presented for the relevant information fields foundon the PHSP final agreement form (FS 711C). Note that familiarity withwildlife habitat objectives of higher-level land use plans in a given areais essential for making prescriptions that are effective at the landscapelevel.

ECOLOGY:

• Note ecologically sensitive areas of uneconomical or difficultharvesting for possible green tree patch retention (see “LeaveTree” Specs, below) — dry sites, wet, low-productivity sites, andriparian areas.

MANAGEMENT OBJECTIVES:

• Use multiple-use management objectives to incorporate wildlifevalues, particularly in areas with high recreational use, withhigh timber extraction, or of particular importance to wildlife.

OTHER RESOURCE VALUES (WILDLIFE):

• Note key wildlife species use in the area, such as Grizzly Bear,Caribou, or nesting raptors.

• Note key habitats, such as riparian areas, wetlands, southaspects, or ungulate winter range.

HARVESTING PLAN:

Silvicultural System:

• Consider partial cutting on very dry sites, in riparian forests,on ungulate winter ranges, or wherever it is technically feasibleand ecologically suitable.

• If recommending clearcut systems, leave buffers along streamsand patches of live and dead trees within a cutblock (see“Leave Tree” Specs, below).

• For any silvicultural system, specify leaving unmerchantablewood on site.

Special Commitments:

• Fish/Forestry and Wildlife considerations in riparian areas.

Seasonal Comments:

Note seasonal considerations on the following points:

• Avoid logging along Caribou migration routes in the spring andfall, and in important feeding areas during the winter.

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• Avoid summer logging or use low-pressure machinery inimportant Caribou wintering areas to minimize disturbance tolichen communities.

• Avoid activities in riparian areas of salmon-producing streamsduring the fall salmon run.

• Avoid spring and early summer harvesting in raptor nestingareas.

• Avoid winter harvesting in ungulate wintering areas.

Rationale for Opening Size/Configuration:

• Vary size of blocks in relation to each other for a givenwatershed.

• Leave strips should be maintained between blocks for as longas possible.

• Consider long, narrow parallel cutblocks in caribou migrationareas.

“Leave Tree” Specs:

Leave trees left for wildlife purposes could include:

• hardwoods

• patches around raptor nests

• patches of poor-quality trees with deformities

• veteran trees

• riparian/wetland areas

• patches in areas of difficult or uneconomical harvesting (e.g.,dry rocky knobs, gullies, wet depressions)

• patches of merchantable trees in uniform blocks

SILVICULTURAL PLAN:

Site Preparation:

• Prescribe low-intensity burns where necessary to increaseforage production and minimize loss or case-hardening of CWD.

• Where mechanical site preparation is recommended, specify aminimum of CWD piling.

Brushing:

• Leave brush along streams, low-productivity microsites, andpatch retention areas.

• Maintain important forage species such as willow, red-osierdogwood, or berry-producing shrubs.

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• Consider spot treatments rather than broadcast treatments.

Stand Tending:

• Avoid thinning stands during the nesting season (May - July).

• Leave a screen of trees along roads.

• Remove slash from obvious game trails.

• Maintain a mix of native tree species.

• Specify killing, but not falling, larger non-commercial trees tocreate snags.

• On wet, brushy sites with high wildlife forage values, considergroup or cluster planting and intensive management ofseedling clusters.

Reforestation Prescription:

• Promote mixed species planting within a cutblock and amongcutblocks in the same area.

• Maintain a hardwood component in stands.

• Consider planting ecologically suitable species that have notbeen well represented in other cutblocks in the area.

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7 SILVICULTURAL INTERPRETATIONSDeveloping and implementing an effective management prescription for aforest site involves integrating and synthesizing many site andoperational factors with the management objectives for the site. The BECsystem provides a framework for organizing and communicating ourknowledge of ecological site factors. It is an essential tool in helping todevelop and refine management prescriptions.

The classification and description of ecosystems presented in this guide,combined with information on relative productivity, site limiting factors,silvics, and silviculture, provide the basis for developing silviculturalinterpretations for ecological site units.

The PHSP is the formal process for integrating these interpretationswith other resource interpretations, operational considerations, andmanagement objectives. The result should be a sound managementprescription that can be monitored over time and assessed against site-specific conditions. Successes and failures can be linked to ecological siteunits and the results used to modify and refine future interpretationsand prescriptions.

This field guide is only one of many references that should be used indeveloping a prescription. There are several recently published reportsand interpretive handbooks available in British Columbia that deal atlength with specific issues such as silvicultural systems, vegetationmanagement, prescribed fire, mechanical site preparation, sitedegradation, slope stability, timber harvesting, pest management, wildlifemanagement, and management for biological diversity. A list of resourcematerials is provided in Appendix 1.

Lavender et al. (1990) is an excellent general reference on the methodsand principles of forest regeneration in British Columbia. As thatpublication illustrates, the amount of information available to forestpractitioners is indeed overwhelming. The role of this field guide is topresent the ecological framework in which to apply this large body ofinterpretive information to the diversity of forest sites found within thePRFR.

The interpretations presented in this chapter relate primarily to themaintenance or enhancement of site productivity for timber production.Specific interpretations include site productivity, limiting factors forproductivity and regeneration, vegetation potential, tree species selectionand stocking standards, reforestation considerations, conifer pests anddiseases, and grass/legume seed mixes for silviculture, range, andengineering. Wildlife interpretations, including a discussion of wildlifehabitat considerations in harvesting and silviculture planning, arepresented in Chapter 6.

To date, most of our silvicultural experience in the PRFR has been witheven-aged silvicultural systems, primarily clearcutting. Over the past 3 - 4years, however, several operational and research trials have beenestablished to examine alternatives to conventional clearcutting, involving

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several types and intensities of partial cutting, followed by natural andartificial regeneration. Preliminary recommendations on the applicationof alternative silvicultural systems in the PRFR will be presented withinthe BEC framework in a future field guide insert. Several referencesdealing specifically with silvicultural systems are listed in Appendix 1.

7.1 Forest Productivity and Regeneration: EcologicalPrinciples

In our classification and description of forest ecosystems, we haveconcentrated on three main components of natural ecosystems: climate,soils, and vegetation. Developing silvicultural interpretations from thisclassification depends on an understanding of these three broadcategories of interacting ecological factors.

This section summarizes some basic concepts of climate, soils, andvegetation needed to understand site productivity and crop treeestablishment, survival, and growth. These principles and a carefulassessment of site characteristics can help the user identify the limitingfactors to regeneration and productivity. From there, managementprescriptions can be developed, designed specifically to address thelimiting factors of the site.

The information presented here is summarized largely from Stathers etal. (1990) and Newton and Comeau (1990). Readers should refer to thesefor a more detailed treatment of these topics.

7.1.1 Climate

Scales of climate

Climatic components (solar radiation, air and soil temperature,precipitation, humidity, and wind) can be evaluated at three main scales:regional climate, local climate, and microclimate.

Regional climate, or mesoclimate, characterizes large areas(biogeoclimatic zones, subzones, and variants) and is not affected by localtopography or vegetation. Local climates are modified by topography(e.g., aspect) and characterize smaller areas (sometimes recognized asbiogeoclimatic phases). Microclimates characterize very small areassuch as individual plant communities or smaller microsites (e.g.,individual seedlings) within them. Local topography andmicrotopography are major determinants of microclimate, while soil andvegetation can both determine and reflect microclimate.

Regional and local climate determines the overriding limiting factors forregeneration and productivity within a subzone (length of growingseason, rainfall, snowpack, etc.) over which we have limited control. Sitetreatments can, however, considerably alter seedling microclimates.

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Solar radiation

The sun’s energy drives biological production. However, only a smallpercentage (< 5%) of the sun’s energy reaching the earth is used inphotosynthesis. Most of the sun’s radiation contributes to heating the soiland air near the ground surface and thus drives the evaporation of waterfrom soil and vegetative surfaces (evapotranspiration). Biomassproduction increases as evapotranspiration rates increase.

At the regional climate level, factors such as latitude, elevation, andcloud cover affect the intensity and duration of solar radiation. At thelocal and microclimatic levels, slope and aspect are most important. Forexample, at 50 degrees north latitude, a 50% slope on a north aspectreceives about 65% of the radiation reaching a flat surface and just over50% of the amount received on a south aspect of similar slope. Similarrelationships hold for north- and south-facing microsites (e.g., mounds).

Air temperature and frost

Temperature near the ground is one of the most important microclimaticfactors affecting seedling establishment, survival, and growth. Micrositecharacteristics have a dramatic influence on air temperature. Largeannual and diurnal temperature variations are familiar to most of us,but equally important is the often dramatic range in temperature thatoccurs at any one time within a few metres of the ground surface. Duringthe day, when solar radiation is being absorbed by the ground surface,temperatures can be 5 - 10° C warmer near the ground than at 2 m abovethe ground. At night there is a net loss of long-wave radiation from theground to the atmosphere and temperatures can be 2 - 5° C cooler atground level that at 2 m above the ground.

Radiation frosts occur when this radiation loss results in surfacetemperatures dropping to below 0° C. The hazard of radiation frost ishighest during the spring and fall because of the long nights (especiallyin the fall) and lower day-time surface heating during these seasons.

The magnitude of the diurnal and elevational temperature differentialclose to the ground surface depends on several climatic and site factors.Cloud cover, humid air, and windy conditions tend to reduce the temper-ature variation near the ground (and thus the frost risk). Air temperaturegenerally decreases with increasing elevation, and high-elevation sitestend to experience greater diurnal and annual temperature fluctuations.

We have already discussed how slope and aspect affect the amount of solarradiation received, which greatly affects air temperature near the ground.Slope angle and position also affect surface air temperatures throughtheir influence on cold air drainage and ponding. When air cools, it flowsdownslope and accumulates in level and depressional areas. This pondingand continued radiative cooling (at night) of cold air on lower slope,depressional, and flat sites results in these sites having a much higher riskof growing season advection frosts than better-drained mid and upperslopes. Cold air ponding can occur both at the local level (valley bottom

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versus adjacent slopes) and microsite level (depressions versus mounds).Cold air ponding often occurs at the bottom edge of clearcuts where airflow is blocked by the forest canopy.

Vegetative cover can dramatically affect surrounding temperatures.Daytime heating and night-time cooling at the soil surface are bothreduced by the shading of vegetative canopies, especially tree canopies.This can effectively remove the temperature differential that wouldotherwise occur within 2 m of the soil surface. The net effect on seedlinggrowth may be positive on frost-prone sites, or negative in cold climates,where day-time microsite temperatures are reduced. However, someshading is generally considered beneficial for early establishment ofnatural regeneration, even in cold climates.

Soil temperature

Soil surface and rooting zone temperatures can dramatically affectregeneration and productivity. In the PRFR, low soil temperature isbelieved to be a significant growth-limiting factor, especially in interiorsubzones. Damage to seedlings from high temperatures (e.g., southerlyaspects that have been slashburned) is much less of a concern in thePRFR.

Although mean annual soil temperature is a function of regional climate,surface soil (and air) temperatures are dramatically influenced bymineral soil and forest floor characteristics. Dark-coloured (e.g., burned)surfaces absorb more radiation than lighter surfaces do, and thus tend tobe warmer. Mineral soils conduct heat into, and out of, the underlyingprofile better than organic soils. Thus, warmer day-time and coldernight-time air temperatures occur immediately above organic surfacesthan above mineral surfaces, all other factors being equal. However, bothsoil and surface air temperatures are strongly affected by soil moisture.Wet soils have a higher heat capacity and thus take longer to warm up.Also, because evapotranspiration consumes a larger proportion ofradiation absorbed by a wet soil than by a dry soil, wet soils (and the airabove them) are generally cooler than dry soils.

Precipitation

The total amount and form of precipitation are largely determined byregional and local climatic factors such as distance from the ocean orother large water bodies, existence of mountain ranges, aspect, andelevation. Localized variation in precipitation may occur as a result oftopography; for example, snow accumulation is greatest in areas of leastexposure to scouring winds (ridge tops versus leeward slopes anddepressions). At the microclimatic scale, variation can occur due tovegetative canopy characteristics and microtopography/surfacecharacteristics. For example, canopy density affects rain and snowinterception and snowmelt, while site features such as surface roughness,occurrence of stumps and logs, and surface darkness affect the accumu-lation, distribution, melting, and downslope movement (creep) of snow.

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Too much precipitation can be as limiting to regeneration andproductivity as too little. The PRFR includes both ends of theprecipitation spectrum. High rainfall combined with low evapo-transpiration rates in the Very Wet, Hypermaritime CWH subzone(CWHvh) on the PRFR’s outer coast results in excess soil moisture onmany sites and moisture deficits on very few sites. In this subzone, animportant component of most management prescriptions should be themaintenance or improvement of soil drainage and aeration. In our Dry,Cool SBS subzone (SBSdk), however, droughts sites are common and theconservation of soil moisture becomes an important issue.

Deep snowpacks are characteristic of high-elevation ESSF and MHsubzones and northern ICH subzones (especially the ICHvc). Snow coveris important for moisture recharge and insulation, but can also be alimiting factor to regeneration where seedlings are damaged by snowpress and snow creep, or where long-lasting snow shortens the length ofthe growing season. Risk of snow damage (broken or deformed stems) isgreatest where wet, heavy snowpacks undergo considerable settling, orwhere downslope movement of dense snowpacks occurs (the risk ishighest on smooth slopes >35%).

Wind

Wind affects forests in many ways. Together with fire and insects, windis an important natural disturbance agent throughout the PRFR. Fromthe canopy gaps created by localized windthrow, to extensive blowdownareas of several hundred hectares, wind has helped to shape foreststructure and age class distribution in many of the region’s subzones.

As outlined earlier, windy conditions help to mix surface air and thusdecrease the risk of frost at night and intense surface heating during theday. Exceptions occur when, for example, cold downslope windsgenerated at high elevations or at the heads of glacial valleys reducetemperatures at lower elevations. Wind can also contribute todesiccation, especially on exposed, droughty sites. In very windyenvironments, such as the exposed outer coast and in subalpine areas,tree form is shaped by the wind.

Although little can be done to control wind, an understanding of local windcharacteristics — such as average velocity and direction, frequency of highwinds, and local phenomena such as funnelling in valleys — is valuablein planning forestry operations to minimize the impact of wind. Cutblockshape and orientation with respect to prevailing winds, for example, canaffect windthrow along the boundaries. Avoiding fine-textured soils withshallow, root-restricting layers when locating cutblock boundaries willalso help to lessen the risk of blowdown.

7.1.2 Soil

Soil includes organic and mineral matter, gas- and water-filled pores, andliving organisms that inhabit it. It is not abiotic. On a human time scale,soil is a non-renewable natural resource. There are physical, chemical, and

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biological properties associated with all soil, and in combination theydescribe the soil ecosystem. Some examples of these properties includetexture, colour, depth, and climate at a soil or its horizons (physical); pHand the amount, concentration, and ratio of nutrients (chemical); and allthe plants and animals that inhabit at soil (biological). Changes in any ofthese properties may induce changes in some or all of the otherproperties — the effect may be imperceptibly small or quite dramatic.The soil is a dynamic ecosystem continuously changing. The changes maybe natural, such as seasonal weather patterns, wildfire, and plantsuccession. Others are human-caused and include harvesting and sitepreparation activities. BEC can help to predict what changes might takeplace in the soil ecosystem because some soil properties are closelyassociated with certain site series (e.g., high water table), and some sitephases are defined to reflect a particular soil property, such as texture.

Some practices associated with harvesting and site preparation candeplete site carbon (energy) and nutrient capital, cause structuraldamage to the soil, or accelerate erosion, reducing productivity to thepoint that site potential is compromised. To understand the effects thatany management activity can have on forest soils, it is necessary toappreciate the nature of the soil ecosystem and its relationship toabove-ground components at the forest ecosystem.

Surface soil material includes the upper solum from the ground surfaceto a depth of 30 - 50 cm, the area in which most biological activity occurs.This includes the forest floor, upper mineral horizons, pore space, andorganisms. Within any site, the nature at the surface soil can be greatlyinfluenced by microtopography (Figure 7.1). The following paragraphsbriefly explain some of the more important features of surface soilmaterial.

Forest floor and humus form

The forest floor (surface organic layer) is typically more heterogeneousthan the underlying mineral layer. In addition to the variation in thedepth and coverage of forest floor and decaying wood, variation in therate of organic matter decomposition also occurs from site to site. This ismanifested in the presence of different humus forms (consult Green et al.1993) that indicate differences in nutrient availability. The three humusform orders — Mor, Moder, and Mull — generally indicate an increasingnutrient content and availability, respectively. Therefore, Mor humusforms predominate on nutrient-medium and nutrient-poor sites, whileModer and Mull humus forms predominate on richer sites.

The forest floor insulates the underlying mineral soil from moisture andtemperature conditions at the soil surface. The magnitude of this effect isrelated to forest floor depth: soil temperature and moisture levelsbeneath deep forest floors fluctuate less throughout the season thanbeneath thin forest floors. This effect may be undesirable in cold climateswhere seedling root growth maybe inhibited by low soil temperatureduring the growing season, but beneficial in warm climates where thepresence of the deep forest floor may help to conserve soil moisture.

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a) Microtopographic variation in forest soils.

b) Variation in surface substrates associated with forest soils.

FIGURE 7.1 Microtopographic variation in surface soil characteristicsand soil climate.

Although poorly decomposed forest floor materials may dry out duringthe growing season, thus providing unfavourable planting spots, well-decomposed forest floor layers can be acceptable planting spots, especiallyfreely drained mounds on very wet sites. On water-deficient sites,planting close to well-decomposed decaying wood may improve wateravailability for seedlings.

Mineral Soil

On most forested sites, mineral soil is found beneath the forest floor. Theremay be an abrupt and clear boundary as in the Mor humus form, or amore gradual one, as in many moder humus forms. In cases where theforest floor is very thin or absent and the first mineral horizon is enrichedin organic matter Ah horizon), the humus form is a Mull. Some sitepreparation techniques disturb or remove the forest floor and the mineralsoil may be exposed. Mixing of forest floor materials with the surfacemineral horizons, especially nutrient-poor, coarse-textured, or very acidicmineral horizons, will generally improve the quality of planting spots.

Soil texture (see Appendix 11) is one of the most important interpretivemineral soil properties and is easily estimated in the field.Coarse-textured (sandy and/or gravelly) soils typically have a low water-and nutrient-holding capacity, but good water drainage and aeration, andare often associated with nutrient-poor and dry sites. Fine-textured (siltyand clayey) soils have high water- and nutrient-holding capacity, butpoorer drainage and aeration, and are often associated with morenutrient-rich and wetter sites. In addition, soil compaction and frostheaving of seedlings occur more frequently in finer-textured soils. Loamysoils are generally ideal because they are intermediate in the aboveproperties.

Coarse fragments (particles >2 mm in diameter) reduce the quality of thetextural properties by lessening the water- and nutrient-holding capacity.Bedrock close to the surface decreases moisture and nutrient content andrestricts rooting. Organic matter in the mineral soil will increase water-and nutrient-holding capacity, improve soil structure, and enhancebiological activity. Well-drained and well-structured mineral soil enrichedwith organic matter is a good indicator of productive microsites andplanting spots.

Soil air and water

A medium-textured soil contains about 50% pore space by volume in themineral portion of the soil. Ideally, about half of the pore space is takenup by air (gases) and the other half by water. The quality of this pore spaceand the air:water ratio can have marked effects on soil productivity. Whenwater drains from soil, it leaves the large pores first while air replaces it.Water in the intermediate-sized pores mixes with salts and becomes thesoil solution that is very important in the transfer of nutrients to plants.Water can be held so tightly to the surface of soil particles in the finest porespaces that plants will wilt and even die unless additional water is added tothe soil. Soils that have a high proportion of small to large pore space are

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often poorly aerated and poorly drained. The relative humidity of soil airis usually 100%, and the carbon dioxide and oxygen concentrations arehigher and lower, respectively, compared to the above-groundatmosphere. Dinitrogen (N2) in soil air can be fixed (hydrogen added,resulting in NH3

+) by numerous free-living or symbiotic soil organisms.This is the primary means of restoring nitrogen to ecosystems throughthe nitrogen cycle. Compaction of soil is the destruction of pore space(large pores are the first to be affected), and will ultimately reduce soilproductivity. Compaction is caused primarily by machinery on medium-and finer-textured soils, when conditions are moist or wet.

Soil organisms

The soil ecosystem contains a diversity of organisms, from vascularplants to rodents and insects, bacteria, and fungi. One cubic centimetreof soil may contain billions of micro-organisms. Nearly all nutrientsrequired for plant growth become available through the variousdecomposing activities of soil organisms, or through symbioticrelationships that some soil-borne organisms have with plants. Soil faunagenerally reduce the particle size of plant and animal detritus, preparingit for smaller organisms to chemically alter. As well, they play animportant role in intermixing organic matter with mineral soil. All theorganisms, including plant roots, help create favourable soil structurethat keeps soils porous. Mycorrhizal fungi can provide nutrients andmoisture to plant species by “extending” root systems, and may provideprotection from disease organisms. Some soil organisms are responsiblefor tree diseases such as root rots.

Shifts in species diversity and populations are common occurrences insoils and may be short- or long-lived. These changes can be caused byfreezing and drying, or by management activities such as prescribedburning. Because we know little about the long-term effects of forestmanagement on soil biology, we are cautious to make species-specificinterpretations. However, the most productive soils are those that are themost biologically active. Therefore, promoting activities that conserve orenhance a diverse population of organisms will ultimately help tomaintain productive soils. Conversely, activities that, for example, reducesoil structure or organic matter will reduce favourable conditions for soilorganisms and contribute to declining productivity.

Microsite and microtopography

A forest is a mosaic of sites and each site is usually a complex ofmicrosites. A microsite is a portion of a site that is uniform inmicrotopography and surface soil materials. It can range in size from lessthan 1 m2 to occasionally over 5 m2. Microsites are ever-changing, as aresult of aggradation or degradation processes associated with water,wind, mass wasting, blowdown, and wildfire, as well as with forestharvesting, site preparation, and stand tending.

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Most sites have several types of microsites, and some of these may bemore appropriate for tree establishment than others. While site quality isused as a criterion for tree species selection, microsite quality should bethe criterion for the selection of actual planting spots. Furthermore, anunderstanding of the relationship between microsite and seedlingsurvival and growth on a particular site is essential to the selection ofthe most appropriate site preparation method.

Mounds and depressions are two principal expressions ofmicrotopography (surface shape) (Figure 7.1). The primary influences onthe microclimatic regimes of mounds and depressions are height andfrequency, along with slope and aspect.

In general, mounds are drier and warmer than depressions. However, themagnitude of the difference depends on the local climate, relief, andaspect of a site, in addition to the material composition of the moundsand depressions. Because of the accumulation of fine organic and mineralmaterials, depressions often have greater concentrations of nutrientsthan do the apices of mounds.

On sites with no major water deficit in the growing season and highprecipitation in fall and winter, depressions can have temporary surfaceponding or a high water table. In such situations, they are less suitablefor seedling establishment and growth than mounds are. On sites in dryand warm climates, where a water deficit is expected early in thegrowing season, depressions can provide more suitable planting spotsthan mounds, especially the south exposure of mounds. The latter,however, can be appropriate microsites in cold and snowy climates, whilethe north exposure of mounds can be suitable in warm climates,particularly on steep, south-facing slopes.

7.1.3 Vegetation

The complex interactions of many soil and climatic factors, together withsite disturbance history, are manifested in the vigour and composition ofthe plant community on a given site. An understanding of vegetation andenvironment relationships and of the adaptations and behaviour ofindividual plant species (species autecology) is fundamental to managingthe vegetation on a site. The term “vegetation management” is most oftenused in the context of controlling competing vegetation duringreforestation. However, the entire forest management prescription shouldreally be thought of as a vegetation management prescription, because itdescribes a series of treatments aimed at manipulating a plantcommunity (the forest) for specific purposes. Depending on sitecharacteristics and management objectives (timber versus wildlife,preferred tree species, etc.), manipulations of that plant community mayvary considerably.

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Vegetation and site diagnosis

Climax vegetation is used as an indicator of site quality, because it isconsidered to be the best integrator of all site factors. This is fundamentalto BEC. The concept of compensating factors is important to understandin this regard. Individual site factors often compensate for one anotherand thus a plant community may encompass a wide range of soil, site,and climatic parameters. This is apparent in the environmental tables inChapter 5. For example, a devil’s club association in most subzones istypically restricted to lower-slope receiving sites. However, this associationextends further up slopes on finer-textured soils, or in wetter, snowierclimates, where soils remain moist throughout the growing season. Sitediagnosis is more difficult in the absence of climax vegetation, becausemany individual site parameters have to be assessed and integrated bythe surveyor, in the context of the seral plant community. The challengewhen interpreting seral communities is separating inherent site factors,such as soil moisture and nutrient regimes, from factors associated withthe disturbance, such as increased light and warmth, and mineral soilexposure. This requires experience on the part of the surveyor.

Plant succession

The gradual change in the structure, composition, and functioning ofplant communities over time is termed “succession”. Primary successionoccurs on previously non-vegetated surfaces such as rock outcrops, freshlydeposited colluvium, or glacial till. Wetland succession resulting from thegradual accumulation of organic matter (peat) on saturated sites isanother example of primary succession. In forestry we are concernedmainly with secondary succession, the sequence of plant communitiesthat develop after a disturbance such as harvesting or wildfire. Manymanagement practices are aimed at manipulating secondary succession.

In most cases, management objectives call for prompt reforestation,where conifers are established immediately following a disturbance. Onsites where initial colonization and biomass production are very rapid,the establishment of desirable crop trees may require large effortsoperationally. Often we are attempting to immediately establish speciesthat are naturally adapted to later successional stages, and thuscompressing into a few years what under natural conditions may havetaken much longer (see Figure 2.2). Pioneer species such as lodgepolepine (on many interior sites) and black cottonwood (on alluvial sites)have thus become more attractive commercial species. These species haveinitially higher growth rates and require less effort to establish thanalternative species (such as spruce and redcedar), which may have moredesirable product characteristics but are naturally adapted to latersuccessional stages and are often slower growing.

Rates and patterns of secondary succession are variable, and for manysites not well understood, except in general terms. We know, for example,that initial colonization progresses faster, and biomass production is great-est, on moist to wet, nutrient-rich sites in all subzones. Total plant cover

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commonly reaches 100% within 3 - 4 years on these sites, whereas totalcover is often less than 50% even after 6 years on slightly dry to freshsites. There is considerable variation by zone, with the fastest rates ofvegetation development occurring in the coastal and transitional CWH andICH zones, and slowest rates in the AT and northern SWB and BWBS.

Predicting the species composition of seven plant communities is partlypossible, but is limited by the considerable chance element that governsthe process. Initial species composition is a function of propagules beingpresent on the site and conditions being suitable for germination/sprouting and growth of these propagules. Propagules originate fromthree main sources: 1) bud banks of species present on the site beforedisturbance; 2) seed banks stored on site (in the mineral soil, forestfloor, and vegetative canopy); and 3) seed rain from adjacent off-siteecosystems.

Bud-banking species can readily resprout from above- and below-groundparts. For example, fireweed and aspen sucker from buds on their roots,thimbleberry and salmonberry sucker from underground rhizomes, andwillows resprout from above-ground buds at the base of the stem. Gener-ally, bud-bankers are capable of much more rapid initial growth thanplants that have to start from seed. While the component of bud-bankingspecies can be predicted to some extent by their occurrence on a sitebefore harvesting, in some cases bud-banking species may form a veryminor component of the mature forest community, but underground rootsor rhizomes may expand very rapidly following disturbance (e.g., fire-weed). Slashburning or mechanical site preparation may delay theregrowth of some bud-banking species for a year or so (e.g., thimbleberry),but such disturbances, unless very severe, rarely prevent (and may actu-ally encourage) their eventual regrowth. The bud-banking species are theeasiest component of the seral community to predict, because they aregenerally (though often in small amounts) apparent in the mature forest.

The seed bank is much harder to predict. It consists of seeds present at thetime of disturbance that are stimulated to germinate. Several disturbancefactors may stimulate seed-banking species to germinate, such as surfacesoil/forest floor mixing, fire, increased surface warming, and light.Although a portion of the seed bank originates from species currentlypresent in the overstory (e.g., lodgepole pine) or understory (e.g., redelderberry), the seed bank often contains species that have long sincedisappeared from the present plant community. Seed-banking speciesinclude thimbleberry, Ribes species, red elderberry, red-osier dogwood, andblack twinberry that have stored seed in the forest floor or soil for severalyears. Another seed-banking species is lodgepole pine, which stores seed inthe canopy until fire comes along to release it and stimulate germination.

Seed rain is predictable to the extent that the seed dispersalcharacteristics of those species composing the surrounding vegetation areknown. Although millions of seeds typically arrive at a cutblock annually,relatively few of them will land on suitable substrates and germinate.Still, the seed rain component can be a major determinant of secondary

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succession, especially on sites that have been severely disturbed. Speciesthat typically colonize via wind-dispersed seed rain include most conifers,red alder, paper birch, and fireweed. Seeds of species such as blueberriesand huckleberries, salmonberry, and salal may be transported onto a siteby animals. However, these species primarily regenerate in canopy gapsand colonize during secondary succession as bud-bankers.

Vegetation potential and vegetation complexes

From the discussion above, it is apparent that although we can useseveral clues from pre-harvest and adjacent stand conditions to predictthe species composition of post-harvest plant communities, the element ofchance hampers precise prediction. We must then generalize about thenature of seral vegetation/environment relationships, based on ourexperience throughout the region. To this end, we have used a ratingsystem for vegetation potential, combined with the concept of vegetationcomplexes described by Canard (1984) and Newton and Comeau (1990),to predict and describe initial post-disturbance succession.

Refer to Section 7.2 for a description of vegetation potential classes(Table 7.1) and vegetation complexes (Table 7.2). A rating of vegetationpotential, together with the expected vegetation complexes, are presentedon a site series basis in the interpretations tables (Section 7.3) for each ofthe subzones/variants of the PRFR. Comments relevant to vegetationmanagement concerns are also provided in these tables.

Impacts of non-crop vegetation

It is important to assess both the beneficial and detrimental effects ofnon-crop vegetation development following harvesting or otherdisturbances. Too often we assume that the net effects on crop treesurvival and growth are negative without looking at the entire picture(see Newton and Comeau 1990 for a more detailed discussion of thistopic).

Specific potential benefits of post-disturbance vegetation developmentare:

• the capture, storage, and cycling of nutrients on site;

• improvement of soil physical and chemical properties, includingnitrogen fixation by species such as alders and legumes;

• prevention of soil erosion, soil puddling, and mass wasting;

• lessened risk of damage to seedlings by certain insects (e.g.,spruce weevil impact is often less under a canopy of alder),browsing wildlife, including small mammals, through theprovision of alternative food sources (small mammal damagemay increase under some circumstances — see below), frost,and intense heat (see Section 7.1.2);

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• improvement of forage values for wildlife and domestic livestock(bird diversity is generally higher in stands having a deciduouscomponent);

• enhancement of stream values by providing protective cover andorganic debris and stabilizing stream banks; and

• contribution to overall species diversity on the site.

The detrimental effects of vegetation development generally centre onimpacts on tree seedling establishment, survival, and growth. Specificimpacts on seedlings are variable, depending on silvical characteristicssuch as shade tolerance. Highly suppressed seedlings typically have thincrowns, reduced leaf area, and large height:diameter ratios. Thesecharacteristics lead to reduced seedling vigour, growth, strength, andcompetitive ability.

Specific potential detrimental effects include:

• reductions in solar radiation reaching seedlings and the ground.Photosynthetically active radiation (PAR) reaching overtoppedseedlings may be reduced by 80% under a vegetative canopy of50% cover. Under a 100% canopy cover, PAR may be reduced by95% or more. Reductions in total solar radiation reaching theground contribute to lower soil and surface air temperatures.Depending on macroclimate, aspect, and other site factors, thismay be detrimental (by shortening the effective growing seasonand delaying bud burst) or beneficial (by protecting seedlingsfrom intense heat and moisture loss).

• reduction in amount of soil water available to tree seedlings.Competition for moisture is not considered to be of majorconcern on most forested sites within the PRFR, with theexception of some sites in the SBSdk, SBPSmc, and BWBSdksubzones.

• reduction in the initial availability of nutrients to tree seedlings.However, nutrients are not lost from the system, but rathertaken up, stored, and recycled by the vegetation. In terms oflong-term site productivity, the net effect may be positive.

• physical damage (deformed or broken stems and branches)caused by falling, bending, or wind-whipped vegetation. Shade-intolerant seedlings overtopped by a vegetative canopy areparticularly susceptible because of their typically largeheight:diameter ratios. The risk of physical damage is increasedunder wet, heavy snowpacks.

• increased risk of small mammal damage, due to the protectivecover provided by vegetation, especially grassy swards andaspen thickets.

• increased spread of noxious weeds such as Canada thistle.

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Assessment, prevention, and control

Assessment and control of competing vegetation has two components:

1. prediction of vegetation potential (based on pre-disturbancesite characteristics and local experience on similar sites) inorder to plan and initiate prescriptions that prevent severecompetition with crop trees.

2. assessment and control (crop tree release) of presentcompetition levels in harvested areas.

This guide is most applicable to the first component: prediction andprevention. Severe competition problems can often be avoided throughthe prediction of site-specific vegetation potential and initiation ofpreventative measures such as:

• use of appropriate silvicultural systems and harvestingtechniques, including pre-harvest vegetation control, whereapplicable;

• use of appropriate site preparation techniques that minimizemineral soil exposure and slow initial vegetation developmentfor 1 - 3 years (prescribed fire as well as mechanical andchemical site preparation methods may be appropriatedepending on site conditions);

• prompt planting (the first growing season after harvest);

• use of healthy, vigorous seedlings of the appropriate stock type(large 2-year-old+ stock) and species; and

• on especially problematic sites with very high vegetationpotential (see Table 7.1, page 7•18), consider cluster planting ofabout 5 seedlings per cluster and reduced stocking, so thatvegetation management treatments can be intensively appliedaround the tree clusters, rather than broadcasting treatmentsover the entire block.

Assessment of existing competition levels (component 2 above) is doneduring silvicultural surveys. Parameters such as percent cover and heightof competitive species in relation to height, diameter, vigour, and physicalcondition of crop trees are recorded and a subjective assessment made asto whether a problem exists. This subjective assessment is considered tobe effective operationally, although some quantitative competition indicesdesigned to refine the process are currently being developed and tested.

Several treatments (either preventative or reactive) are available forcontrolling competing vegetation. Broad categories of treatments are:chemical, manual, motor-manual, mechanical, and biological (grazing).The choice of treatment will depend on many factors including costs,feasibility, and effectiveness on the specific site conditions, perceivedrisks to other site resources, and other social concerns (see Newton andComeau 1990).

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Specific information on the autecology and response to managementtreatments of 35 common British Columbia plants can be found in Coateset al. (1990) and Haeussler et al. (1990). Other relevant publications arelisted in Appendix 1, part 2.

7.2 Interpretations Tables

Interpretations tables are presented for 20 biogeoclimatic units occurringin the PRFR. The purpose of the tables is to summarize, on a site seriesbasis within each subzone or variant, our current knowledge of forestproductivity and selected management interpretations. The tables aredesigned to promote an ecological approach to developing a managementprescription, through identifying and addressing the factors that limitproductivity and regeneration on each of the site series within a subzone.

The maintenance or enhancement of site productivity for timberproduction is the major theme of the tables. Specific interpretations arepresented under five categories: site productivity, limiting factors forproductivity and regeneration, vegetation potential and complexes, treespecies selection guidelines, and reforestation considerations. Each ofthese categories in the tables is explained below.

Note that the tables do not contain “cookbook” prescriptions. In mostcases there are many alternative treatments to choose from to addressthe concerns and recommendations contained in the tables. These tablesshould be used in combination with the many interpretive handbookslisted in Appendix 1, part 2. The final prescription must considersite-specific conditions, operational constraints, local experience, andmanagement objectives for the site.

7.2.1 Site series

Site series are designated by their number code. The tables are designedto be used in conjunction with the site identification and descriptioninformation presented for each subzone/variant in Chapter 5.

7.2.2 Productivity

Tree species productivity varies considerably throughout the PRFR.Biogeoclimatic subzone and site series within subzones account for muchof this variability, although we have only recently begun to quantifythese relationships. The grey bar at the top of the column represents ascale of site index from 0 to 40 m at breast height age 50 yrs (BHA 50).The placement of tree species codes14 in the grey boxes below indicatemean site index by species for each of the site series. Where informationis lacking for a species, or where a species does not generally occur in asite series, it is not included in the site index boxes.

14 Tree species codes as in Appendix 3.

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This column in the tables portrays our current knowledge of the range insite index (BHA 50) of natural stands, within a biogeoclimatic unit. It isthus an indication of relative productivity among the site series makingup a subzone/variant.

Ecological site index relationships were derived from several data sources,and data quantity and quality vary considerably by subzone. Height/agedata have been collected from more than 1000 ecosystem sample plotsthroughout the region over the past 15 years. Because these plots weredone mostly in mature and old-growth stands, with trees generally over100 years old and often much older, these data yield the least reliableestimates of site index at age 50. More recently, sampling has been car-ried out in research by the Forest Service and the University of BritishColumbia (e.g., Wang et al. [1992]) in younger second-growth stands withinthe region. These data have yielded better site index estimates for somesubzones (SBSmc and dk, ICHmc, ESSFmc, CWHvm and vh). Data fromInventory Branch permanent sample plots have also been used. In allcases, the most recent site index (BHA 50) curves were used for the siteindex calculations (Thrower and Nussbaum 1991; Thrower et al. 1991).

For simplicity, statistical confidence is not portrayed for the site indexmeans presented in the tables. Values represent our best estimates fromavailable data and experience within the subzone/variant. In some cases,where little or no data exist, values are either estimated, based on datafrom ecologically related subzones/variants, or not provided at all for oneor more of the species. Sources of data are given in the table footnotes. Itis important to note that site index boxes are included to portray generalsite index ranges and trends within subzones/variants. They should notbe considered precise estimates. Further sampling is planned to improvethe data base for ecological site index relationships, and these tables willbe updated in the future.

7.2.3 Limiting factors for productivity and regeneration

This column highlights the site factors most significant in limitingproductivity and regeneration for each of the site series. This informationforms the basis for prescription development. Possible limiting factorsinclude:

• soil moisture (sites with too little or too much moisture);

• soil nutrients (sites with low total amounts of stored nutrientsor sites with low nutrient availability; for example, sites withthick Mor forest floors may have a large nutrient capital, butlow availability);

• soil temperature (sites with cold soils due to macroclimaticfactors and/or soil characteristics such as excess moisture andthick, insulating forest floors);

• air temperature (sites prone to cold air ponding and frost);

• deep, long-lasting snowpacks;

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• root restrictions (sites with compacted horizons, bedrock, orwater tables within 30 cm of the soil surface); and

• competing vegetation (sites with high to very high rating forvegetation potential) (see next category).

Basic principles related to these limiting factors are discussed in detail inSection 7.1.

7.2.4 Vegetation potential and complexes

In this column, a rating of vegetation potential and a listing of vegetationcomplexes are provided for each of the site series.

Vegetation potential describes, in relative terms, the predicted rate ofherb and shrub development following disturbance. Four classes aredefined and described in Table 7.1. The ranking can be used for bothcompeting vegetation and shrub/herb forage interpretations (the rankingshould not be used for berry production or lichen forage interpretations).

Twenty-two major vegetation complexes occurring on harvested siteshave been described in British Columbia (Conard 1984; Newton andComeau 1990). All but one of these complexes occurs in the PRFR.

Vegetation complexes are described in Table 7.2. Each complex consists ofa list of species that tend to be associated with one another on ecologicallysimilar sites. The lists have a silvicultural bias and thus emphasize speciesthat may potentially affect crop tree growth (positively or negatively).However, the complexes are also useful for assessing potential wildlifeforage values. We have modified the lists somewhat to make them moreapplicable to the PRFR. Note that not all the species in each complexshould always be expected to occur together on a given site. Depending on

TABLE 7.1. Vegetation potential classes

Class Description

Low Slow initial rate of herb and shrub development following disturbance. Little orno need for controlling vegetation to ensure adequate regeneration. Competitionfor moisture may be important on some dry sites.

Medium Moderate initial rate of herb and shrub development. Generally little need forcontrolling competing vegetation, although sites should be reforested promptly.

High Fast initial rate of herb and shrub development. Generally a need to plantpromptly following harvest and to plan (in advance of harvest) on controllingvegetation development to ensure successful regeneration.

Very High Extremely fast initial rate of herb and shrub development. Successful coniferousregeneration will require prompt planting with large, healthy, vigorous stock, andspot or broadcast treatment of competing vegetation. Sites with very highvegetation potential should be considered for hardwood or mixedwoodmanagement (e.g., floodplain sites).

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TABLE 7.2. Major complexes of competing vegetation in the PRFR(modified from Newton and Comeau 1990)

Seral BiogeoclimaticComplex Major species origina zone Sites

CW Populus balsamifera SR/BB ICH FloodplainsCottonwood Lonicera involucrata BB/SB SBS

Cornus stolonifera BB BWBSSambucus racemosa BB/SBRubus parviflorus BB/SBAlnus crispa ssp. sinuata BB/SRAlnus tenuifolia BB/SRCalamagrostis canadensis BB/SRCinna latifolia BB/SB?/SR?Symphoricarpos albus BB/SB

CA Populus balsamifera SR/BB CWH FloodplainsCottonwood-alder Alnus rubra SR/SB(BB)

Rubus spectabilis BB/SBCornus stolonifera BB/SBOplopanax horridus BBSambucus racemosa BB/SBRubus parviflorus BB/SBLonicera involucrata BB/SBRibes bracteosum SB(BB)

MH Populus tremuloides BB ICH VariousMixed hardwood Populus balsamifera SR/BB SBS

Betula papyrifera SR/BB BWBSSalix spp. BB/SRAlnus tenuifolia BB/SRAlnus crisps ssp. sinuata BB/SR

AS Aspen Populus tremuloides BB ICH VariousSBSBWBS

BP Populus tremuloides BB SBS Fresh to moistBoreal poplar Populus balsamifera SR/BB BWBS

RS Alnus rubra SR/SB(BB) CWH Fresh to wetRed alder - shrub Rubus parviflorus BB/SB

Rubus spectabilis BB/SBSambucus racemosa BB/SBOplopanax horridus BBRibes spp. SB(BB)Polystichum munitum BB(SR?)Athyrium filix-femina BB(SR?)

SB Rubus spectabilis BB/SB CWH Fresh to wetSalmonberry Rubus parviflorus BB/SB

Ribes spp. SB(BB)

a BB, SB, and SR refer to bud banker, seed banker, and seed rain, respectively; definedin Section 7.1.3. Sources: Haeussler et al. (1990); Stickney (1986); Thomson et al.[1993].

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TABLE 7.2. (Continued)


SA Salal Gaultheria shallon BB CWH Very dry to wet

MS Mixed shrub Rubus parviflorus BB/SB ICH Fresh to wetRubus idaeus SB/BB ESSFLonicera involucrata BB/SB SBSAcer glabrum SR/BBAlnus crispa ssp. sinuata BB/SRPaxistima myrsinites BB/SBSambucus racemosa BB/SBOplopanax horridus BBSalix spp. BB/SRCornus stolonifera BB/SBEpilobium angustifolium BB/SR/SBAthyrium filix-femina BB(SR?)Pteridium aquilinum BB(SR?)Symphoricarpos albus BB/SB

ES Ericaceous Menziesia ferruginea BB/SR CWH, ICH Dry to moistshrub Vaccinium spp. SR/BB ESSF

(Rhododendron albiflorum) BB(SR) MH

DA Dry alder Alnus crispa BB/SR SBS Dry to freshEpilobium angustifolium BB/SR/SB SBPS(Calamagrostis rubescens) BB(SR)

WA Wet alder Alnus crispa ssp. sinuata BB/SR ICH WetAlnus tenuifolia BB/SR SBSRubus parviflorus BB/SB BWBSLonicera involucrata BB/SB ESSFCalamagrostis canadensis SR/BBAthyrium filix-femina BB/SRDryopteris expansa BB(SR?)

DS Dry shrub Amelanchier alnifolia BB/SB ICH Dry to freshPaxistima myrsinites BB/SB SBSShepherdia canadensis BB/SB BWBSSymphoricarpos albus BB/SB SBPS

WI Willow Salix spp. BB/SR ICH, CWH Moist to wetESSFSBSBWBSSBPS

PI Pinegrass Calamagrostis rubescens BB(SR) SBS Dry to freshSBPS

a BB, SB, and SR refer to bud banker, seed banker, and seed rain, respectively; definedin Section 7.1.3. Sources: Haeussler et al. (1990); Stickney (1986); Thomson et al.[1993].

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TABLE 7.2 (Continued)


RG Reedgrass Calamagrostis canadensis SR SBS Moist to wetBWBS(ICH)(ESSF)

FN Fern Athyrium filix-femina BB(SR?) ICH, CWH Fresh to wetDryopteris expansa BB(SR?) ESSF, MH

SBSBWBS

BN Bracken Pteridium aquilinum BB(SR?) ICH Dry to wetCWH

FW Fireweed Epilobium angustifolium BB/SR/SB CWH Dry to wetICHESSFSBSSBPSBWBS

SH Valerians sitchensis BB/SR ESSF Fresh to wetSubalpine herb Senecio triangularis BB/SR

Veratrum viride BBHeracleum lanatum BB/SREpilobium angustifolium BB/SR/SB

IG Domestic grasses ICH VariousIntroduced ESSFgrasses SBS

BWBS

a BB, SB, and SR refer to bud banker, seed banker, and seed rain, respectively; definedin Section 7.1.3.

Sources: Haeussler et al. (1990); Stickney (1986); Thomson et al. [1993].

local conditions, species dominance will vary considerably. To help userspredict which species are likely to be important, we have included noteson seral origin (bud bank, seed bank, or seed rain) for each of the speciesin the lists.

For a more complete discussion of the factors to be considered inpredicting plant succession following disturbance, refer to Section 7.1.3.The potential beneficial and detrimental effects of non-crop vegetationare also summarized in that section.

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7.2.5 Tree species selection guidelines

In this column, tree species selection guidelines are presented for each ofthe site series. A province-wide correlation of tree species selection andfree growing stocking standard guidelines has just been completed(Silviculture Interpretations Working Group 1993). The guidelinespresented here are based on this correlation. The stocking standards arepresented separately for each subzone in Appendix 17. These guidelineswere developed with timber (sawlog) production as a primarymanagement objective, and may require modification on a site-specificbasis to meet non-timber resource objectives (through the PHSP process).

The ecological suitability of each tree species for regeneration within abiogeoclimatic unit was evaluated on a site series basis using thefollowing three criteria (Klinka and Feller 1984):

• Maximum sustainable productivity. The relativeproductivity of each tree species was evaluated for each siteseries.

• Crop reliability. The relative susceptibility to natural hazardswas evaluated for each tree species to determine which speciesprovided the most reliable choices for a future crop.

• Silvicultural feasibility. Ecologically viable tree species wereevaluated, based on accumulated silvicultural experience, todetermine whether they were able to produce sawlogs in a cost-effective manner on each site series within an acceptablerotation length.

Based on the above evaluation, each tree species was assigned to one ofthree categories (the tree species codes in Appendix 3 are used to denotethe species in the tables):

Primary species are listed first (in alphabetical order) and areunbracketed. These species are ecologically acceptable and have thehighest rating for productivity, reliability, and silvicultural feasibilityunder the average conditions for a site series. Primary species cangenerally be managed an a major component in a stand.

Secondary species are listed (alphabetically) in square brackets afterthe primary species. These species are ecologically acceptable, but ranklower than primary species for productivity, reliability, and/orsilvicultural feasibility. Depending on the nature and extent of theselimitations, secondary species can be managed as either major or minorcomponents in the stand.

Tertiary species are listed last in round brackets. Tertiary species areecologically acceptable, but rank lower than primary or secondary speciesfor productivity, reliability, and/or silvicultural feasibility. Depending onthe nature of their limitations and on local conditions, tertiary species arenormally only suitable as a minor component within a stand (20 - 30%),or as a larger component in a few localities, generally on a trial basis.

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Restrictions or limitations may apply to primary, secondary, or tertiaryspecies and are indicated either by footnotes (if the restriction appliesthroughout the subzone), or by comments in the adjacent column entitledReforestation Considerations (see Section 7.2.6 below). Restrictions orlimitations may relate to soil and site factors (including microsite),climate (including susceptibility to frost and snow damage), geographicand elevational range, pest hazard, and productivity. It is important thatfootnotes and comments under Reforestation Considerations be checkedcarefully when the suitability of each of the species is being assessed.

To help users determine species suitability in relation to the site limitingfactors and restrictions highlighted in the tables, a ranking of ecologicaltolerances and nutritional requirements of the major tree speciesoccurring in the PRFR is presented in Figure 7.2. The table can helpusers choose the species best able to tolerate site-specific limitations suchas shade, frost, snow, drought, high water tables, and low nutrientavailability. Note that the ranking is an average across all biogeoclimaticunits in which the species occurs.

Hardwood species (Hard.) that occur naturally (and reach tree size)on each of the site series are also included in the tables. They are notincluded in the primary, secondary, and tertiary designations, however,because of the timber- (sawlog-) oriented objective of these guidelines.Hardwood species may not be used to fulfill basic silviculture obligationsunless this is specified in the approved Land and Resource ManagementPlan. On many floodplain sites and some rich, seepage sites, wherevegetation potential is very high and/or there is a high risk of floodingand erosion, hardwoods may be considered the best species to regenerate.This will be noted under Reforestation Considerations. Note also thatthere are many potential benefits to maintaining a hardwood componentin the stand (see Sections 6.3 and 7.1.3).

Tree species prescription

The tree species selection guidelines in the interpretations tables providespecies recommendations that are used with other information to developthe PHSP. Under the Silviculture Regulation, a PHSP must contain bothfree growing stocking standards (Appendix 17) and a designation ofpreferred and acceptable species. Preferred and acceptable species aredefined as follows:

• Preferred species. Preferred species are ecologically suited tothe site, and management activities are primarily aimed atestablishing these species. The characteristics of these speciesare consistent with the desired timber and non-timberobjectives for the site.

• Acceptable species. Acceptable species are ecologically suitedto the site, but management activities are not aimed atestablishing them.

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a Tree species codes as in Appendix 3.

FIGURE 7.2 Relative ranking of ecological tolerances and nutritionalrequirements for major tree species in the PRFR.(Information based on Klinka et al. (1990) and ecologicalfield work in the PRFR.)

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Preferred and acceptable species may be selected from the primary,secondary, or tertiary categories, provided the species restrictions havebeen addressed and the species meet the management objectives for thesite.

The following procedures should be followed in the development of a treespecies prescription:

1. Describe the site and identify the biogeoclimatic unit and siteseries. Stratification into two or more distinct ecological unitsmay be required.

2. Review the tree species selection guidelines for the site series inquestion. In transitional areas, review recommendations forneighbouring units. Consider primary, secondary, and tertiarydesignations, footnotes, and other comments in theinterpretations table.

3. Consider management objectives, timber production goals, andintegrated resource management goals.

4. Check local site conditions and assess whether speciesrestrictions and limitations apply to the site in question. Assesslocal performance of recommended species.

5. Estimate the potential (species composition, stocking, vigour) ofadvance and post-logging natural regeneration.

6. Evaluate the feasibility of establishing and maintaining therecommended species and addressing relevant restrictions andlimitations, given existing operational constraints.

7. Determine preferred and acceptable species (or speciescombination) and their site preparation and regenerationrequirements.

Species mixes

Species diversity should be maintained both an the landscape and standlevel. It may be impractical (and silviculturally or biologicallyinappropriate) to maximize diversity an the stand level, but within alandscape unit (e.g., a watershed or planning area) proper planningshould ensure that natural levels of tree species diversity aremaintained. Such diversity will increase the resilience and resistance ofsecond-growth forests to such hazards as insects, diseases, and changingclimates. This diversity will also enhance habitat values for a variety oforganisms.

Species mixes are also encouraged at the stand level, but species shouldbe chosen that complement one another in terms of utilization orenhancement of site resources. Potential benefits and some examplemixes include:

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• enhanced yields through more complete use of availablegrowing space (a less shade-tolerant species could be chosen asthe major component and a more shade-tolerant species as theminor component [e.g., Ss/Ba, Ss/Cw, Pl/Hw, Pl/Sxw, Pl/Sxw,Pl/Bl, Sxs/Cw, Sxw/Bl] );

• maintenance or improvement of soil nutrient status (a specieshaving basic, nutrient-rich litter could be combined with amajor crop species having more acidic, nutrient-poor litter; suchcombinations could include a deciduous component — Hw/Cw,Sxs/Cw, Pl/Bl, Pl/At, Sxw/At, Sx/Ep);

• improved stand reliability from pest hazard reduction andenhanced windfirmness (e.g., a Cw component will increasewindfirmness; Ba and Cw should be favoured over Ss and Hw inareas of the CWH having high porcupine hazard, and Bafavoured over Ss in areas of high weevil hazard);

• higher wood quality in mixed stands because of increasednatural branch pruning; and

• increased overall species and structural diversity of the standas a result of species mixes. This will enhance the diversity ofhabitats and other organisms on site.

Additional information on silvical characteristics of tree species can befound in Krajina et al. (1982) and Klinka et al. (1990).

7.2.6 Reforestation considerations

This column summarizes management considerations relevant to treespecies selection and site limiting factors. Species restrictions andlimitations specific to a site series or phase (e.g., soil drainage and frost)are presented here. Species restrictions/limitations that apply to theentire subzone or variant (e.g., moose browse on Bl in the SBSmc2) arefootnoted at the bottom of the table.

This column highlights management considerations that should beaddressed in the PHSP to maintain or improve second-growthproductivity for timber production. Comments are geared toward typicalor average site conditions for the site series but may, in some cases, bespecific to a site phase. These reforestation considerations, together withthe wildlife habitat considerations presented in Chapter 6, should set thestage for developing a PHSP; they are not in themselves prescriptions.Prescriptions must be site-specific, considering actual site conditionstogether with management objectives, including resource values otherthan timber. In most cases there are several different ways of addressingsite limitations and thus several different prescriptions that will addressthe reforestation considerations presented here. This information shouldbe used in combination with specific interpretation handbooks (Appendix1) and local experience in developing a prescription.

Silviculture

7• 26

Slashburning severity guidelines (Trowbridge et al. 1989) arepresented for each of the site series. These guidelines are based on theamount of fuels consumed and suggest the range of acceptable severity ofa fire required to meet management objectives such as vegetation control,creation of plantable spots, ease of planter access, nutrient conservation,and enhancement of soil temperature. A range of acceptable slashburningseverity levels (SSL) is given for each site series using the five-classsystem outlined in Table 7.3.

The slashburning severity levels are based on absolute duff (F andH horizons) consumption and percent slash reduction for sizeclasses <7 cm and >7 cm. These fuel categories can be measured or, withexperience, visually estimated, and appear to be reasonably justifiedparameters for site-specific fire management planning and assessments.

The SSLs that appear in the interpretation tables are suggested for therange of average circumstances encountered. However, some propertiessuch as forest floor depth will vary, and site-specific prescriptions mustaccount for this variation. For example, where the forest floor is thinnerthan expected for a particular site series, then the SSL should belowered. Prescribed burning is not recommended on Folisols or shallowmineral soils over bedrock, or in dry, nutrient-poor ecosystems. No SSLshave been suggested for site series where prescribed burning is highlyimpractical.

TABLE 7.3. Slashburning severity levels and approximate fuelconsumption

Severity level (SSL) Fuel consumption

Duffa Slash ( % )

<7cm >7cm0 (no burning) -- -- --

1 0 cm 40 15(moss/litter only)

2 1-2 cm 50 20

3 2-5 cm 60-70 30

4 5-8 cm 80 40

5 8-15 cm 90 50

a “Duff” refers to the F and H horizons and does not include the litter layer.

Silviculture

7 • 27

BWBSdk1 Interpretations Tablea

Productivityb VegetationSite Site index - ht (m) at 50 yr Limiting factors for potential &series 0 10 20 30 40 productivity and regeneration complexesc

01 Pl Cold soils. Moisture and nutrient MediumSw deficits on some sites. Root restrictions AS, BP, DS,

on compacted tills. FW, CC

02 Pl Severe moisture and nutrient deficits. LowSw Root restrictions on shallow soils over

bedrock.

03 Pl Moisture and nutrient deficits. Root LowSw restrictions on shallow or fine-textured

soils.

04 Pl Very cold soils. Frost/cold air. Moisture Low Sw and nutrient deficits on most sites.

05 Pl Moisture deficits on some sites. MediumSw AS, BP, DS,

FW, MH

06 Pl Cold soils. Competing vegetation. Medium - HighSw Frost/cold air. BP, MH, FW

07 Pl Very cold, wet soils. Nutrient deficits. HighSw Frost/cold air. Competing vegetation. WI, MH

Rooting restricted by high water tables.

08 Pl Cold, wet, often poorly aerated soils. Very HighSw Frost/cold air. Rooting restricted by CW, WA, WI,

high (but fluctuating) water tables and RGfine textures. Competing vegetation.

09/10/11 Pl Saturated, very cold soils with poorSw aeration. Rooting restricted by high Medium

water table. Frost and cold air ponding. WI

a Refer to Section 7.2 for an explanation of each category in the table. b Site index estimates are based on Lewis (1988) and unpublished Ministry of Forests data.

There has been only limited site index sampling in the BWBS zone.c Vegetation potential and complexes are described in Section 7.2.4, page 7•18.

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7• 28

Tree speciesselectionguidelinesd Reforestation considerations

Pl Sw Pl should be favoured on submesic sites, south aspects, and glaciofluvial[Bt] landforms. Risk of frost damage on Sw (lower slope, valley bottom sites). Soil(Sb) temperature and natural regeneration will be enhanced by some reduction orHard: At Ep mixing of LFH and mineral soil exposure (this will also encourage hardwood

expansion when present in mature stand). Fine-textured morainal soils have higherpotential for compaction/windthrow; harvest during dry periods or winter.SSLe 1-3 (depending on aspect and moisture regime).

Pl Marginal sites for timber production. Avoid logging. Conserve thin LFH for(Sb Sw) moisture and nutrient retention. These sites will be slow to regenerate. SSL 0.Hard: At

Pl Sw should be limited to moister microsites. Natural regeneration of Pl should be[Sw] encouraged by a light mechanical treatment (drag scarification) provided cones/Hard: At seeds are present in sufficient quantity. Expect high mortality of planted seedlings

(drought). SSL 0-1.

Pl Marginally productive, cold, frosty sites; avoid logging. These sites will be slow(Sb Sw) to regenerate. SSL 0-1.Hard: At

Pl Sw Similar considerations to 01 (above). 05 appears to be more productive than 01,[Bl] perhaps reflecting a more recent fire history and thinner feathermoss carpet(Sb) (warmer soils, greater nutrient availability). Favour Sw on moister examples.Hard: At Ep SSL 1-2; burning should not be required.

Pl Sw Risk of frost damage on Sw. Soil temperature and nutrient regimes will be en-[Bl] (Sb) hanced by reduction/mixing of LFH, but patch scarification preferred in order toHard: Acb At Ep minimize aspen competition and soil compaction. Sites should be planted

promptly with vigorous stock. SSL 2-3.

Pl Sb Sw These are marginally productive sites that, if disturbed, will be slow to regenerateHard: At due to seasonally high water tables and brush competition. Plant promptly on

raised microsites (artificial or natural). Risk of frost damage on Sw. SSL 1-3.

Sw Pl is limited by shade intolerance and saturated soils. Sw may be damaged by[Pl] frost. Plant sites promptly with large, sturdy stock. Assess/control competing(Sb) vegetation. Minimize mineral soil exposure by patch scarifying or mounding toHard: Acb At Ep establish seedlings. Elevated microsites are preferred planting spots (drainage,

cold soils, frost). Consider cluster planting (see page 7•15) and reduced stocking.Sites often have high risk of compaction and windthrow (finer textures, high watertables) and surface erosion (fluvial sites). SSL 3-4. See Chapter 6 for wildlifehabitat considerations in riparian areas.

Pl Sb Sw These sites are very marginal for timber production and should not be logged.Hard: Acb At High risk of frost damage on Sw. Choose elevated microsites for planting.

d Species are in alphabetical order within primary, secondary [ ], and tertiary ( ) categories. See Section 7.2.5, page 7•22. Tree species codes are described in Appendix 3.

e Slashburning severity levels (SSL) are described in Section 7.2.6, page 7•27.

BWBSdk1

7 • 29

BWBSdk2 Interpretations Tablea


01 Pl Cold soils. Moisture and nutrient MediumSw deficits on some sites. Root restrictions AS, BP, DS,

on compacted tills. FW, MH

02 Pl Severe moisture and nutrient deficits. LowSw Root restrictions on shallow soils over

bedrock.

03 Pl Very cold soils. Frost/cold air. Moisture LowSw and nutrient deficits on most sites.

04 Pl Very cold, damp soils with thick LFH LowSw (Mors) that limit nutrient availability.Sb Frost/cold air.

05 Pl Moisture deficits on some sites. Medium (High)Sw AS, BP, FW,

DS, MH

06 Pl Cold, wet, often poorly aerated soils. Very HighSw Frost/cold air. Rooting restricted by CW, WA,

high (but fluctuating) water tables and WI, RGfine textures. Competing vegetation.

07/08 Pl Saturated, cold soils with poor aeration. MediumSw Rooting restricted by high water table. WI, RG

Frost and cold air ponding.

a Refer to Section 7.2 for an explanation of each category in the table. b Site index estimates are based on Lewis (1988) and unpublished Ministry of Forests data.

There has been only limited site index sampling in the BWBS zone. c Vegetation potential and complexes are described in Section 7.2.4, page 7•18.

Silviculture

7• 30


Pl Sw Pl should be favoured on submesic sites, south aspects, and glaciofluvial(Sb) landforms. Risk of frost damage on Sw (lower slope, valley bottom sites). SoilHard: At Ep temperature and natural regeneration will be enhanced by some reduction or

mixing of LFH and mineral soil exposure (this will also encourage hardwoodexpansion when present in mature stand). Fine-textured morainal soils have higherpotential for compaction/windthrow; harvest during dry periods or winter.SSLe 1-3 (depending on aspect and moisture regime).

Pl Marginal sites for timber production. Avoid logging. Conserve thin LFH for(Sb Sw) moisture and nutrient retention. These sites will be slow to regenerate. SSL 0.Hard: At

Pl Marginally productive sites on cold, droughty, frosty sites; avoid logging. These(Sb Sw) sites will be slow to regenerate. SSL 0.Hard: At

Pl Sb Sw These are marginally productive sites that, if disturbed, will be slow to regenerate[Lt] due to seasonally high water tables. Plant promptly on raised microsites (artificialHard: At or natural). Risk of frost damage on Sw. SSL 2-3

Pl Sw Similar considerations to 01 (above). 05 often has an At component and lushHard: At Ep shrub layers that will expand following disturbance. Favour Sw on moister

examples. SSL 1-2. Sites should be planted promptly.

Sw Pl is limited by shade intolerance and saturated soils. Sw may be damaged by[Pl] frost. Plant sites promptly with large, sturdy stock. Assess/control competing(Sb) vegetation. Minimize mineral soil exposure by patch scarifying or mounding toHard: Acb At Ep establish seedlings. Elevated microsites preferred planting spots (drainage, cold

soils, frost). Consider cluster planting (see page 7•15) and reduced stocking. Sitesoften have higher risk of compaction and windthrow (finer textures, high watertables) and surface erosion (fluvial sites). SSL 3-4. See Chapter 6 for wildlifehabitat considerations in riparian areas.

Lt Pl Sb Sw These sites are very marginal for timber production and should not be logged.High risk of frost damage on Sw. Choose elevated microsites for planting.

d Species are in alphabetical order within primary, secondary [ ], and tertiary ( ) categories. SeeSection 7.2.5, page 7•22. Tree species codes are described in Appendix 3.


BWBSdk2

7 • 31

CWHvh2 Interpretations Tablea


01 Hw Nutrient availability limited by deep MediumCw Mor humus forms. Excess soil moisture SA, ES, BN

due to hypermaritime climate.

02 Pl Severe nutrient deficits and root LowCw restrictions on shallow soils. Wind

exposure.

03 Hw Nutrient deficits and root restrictions on MediumCw shallow soils over acidic bedrock. SA

04 Hw Slope stability. Root restrictions on 04b. LowCw ES

BaSs

05 Hw Slope stability. Root restrictions on 05b. Medium Cw Competing vegetation. RS

BaSs

06 Hw Slope stability. Competing vegetation. HighCw Root restrictions on 06b. RS, SB

BaSs

07 Hw Slope stability. Competing vegetation. Very HighCw Root restrictions on 07b. RS, SB

BaSs

a Refer to Section 7.2 for an explanation of each category in the table. Interpretations for activefluvial ecosystems (08, 09, 10) are presented on page 7•46.

b Site index estimates are based on unpublished Ministry of Forests data; very limited data forsite series 02, 03, and 05.

c Vegetation potential and complexes are described in Section 7.2.4, page 7•18.

Silviculture

7• 32


Cw Hw Ba and Ss should only be considered on nutrient-medium sites (richer bedrock(Ba Pl Ss Yc) types). Pl suitable on the poorest sites (acidic bedrock). On the mineral phaseHard: Dr (01a), productivity may be enhanced by mounding/mixing of LFH/mineral

horizons (some site disturbance will likely be beneficial). There is less opportunityto improve productivity on the lithic (01b) and peaty (01c) phases. Guard againstincreasing soil moisture by impeding natural drainage patterns. SSLe 3-5; burningoften not feasible.

Pl Marginal sites for timber production; avoid logging. SSL 0.[Cw Yc]

Cw Hw Pl Often marginally merchantable. Avoid excessive disturbance, especially on 03b.Hard: Dr SSL 0-3.

Ba Hw Ss These sites often occur on steep colluvial slopes where mechanical disturbance[Cw] should be minimized. There is often abundant advance regeneration (mostly Hw)(Yc) and natural regeneration of Hw can be expected. Ba and Ss should be favoured onHard: Dr richer bedrock types. Cw may be favoured on unstable/windy slopes (rooting habit

offers stability). SSL 1-3.

Ba Cw Ss Similar consideration to 04 above. Hw becomes a secondary species and Cw a[Hw] primary species to reflect the richer site conditions (base-rich bedrock) associated(Yc) with this unit. Hw can be favoured where LFH is thick (>20 cm). SSL 1-3.Hard: Dr

Ba Cw Ss Hw should only be actively managed for on sites with thick (>20 cm) LFH. 06 and[Hw] 07 often occur as a complex, with 06 on the more freely drained sites and 07 on(Yc) the wetter, lower slopes and adjacent to small streams. These productive sitesHard: Dr require careful planning to avoid degradation and brush problems. Log during

driest season with minimal ground disturbance. Dr will be quick to invade dis-Ba Cw Ss turbed sites from adjacent stands; control seed sources (girdling, hack and squirt).[Hw] Plant sites promptly with large, sturdy stock. Assess/control competing vegetation.(Yc) SSL 3-4; successful burn may be difficult to achieve, especially in 07.Hard: Dr



CWHvh2

7 • 33

CWHvh2 Interpretations Tablea (cont.)


11 Hw Saturated, peaty soils restrict rooting, MediumCw nutrient availability, and productivity. SA, ES

Pl

12 Hw Saturated, peaty soils severely limit MediumCw rooting, nutrient availability, and SA

Pl productivity.

13 Hw Saturated, poorly aerated soils limit MediumCw rooting and productivity. SA, SB

14, 15, no information Extreme exposure to wind and ocean Medium16 spray. Root restrictions in 14 and 15. SA

18, 19 no information Fluctuating, brackish water tables. Wet, Mediumpoorly aerated soils. SA, SB

a Refer to Section 7.2 for an explanation of each category in the table. b Site index estimates are based on unpublished Ministry of Forests data; very limited data for

site series 11 to 13. c Vegetation potential and complexes are described in Section 7.2.4, page 7•18.

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7• 34


Cc Hw Yc Bog forests are marginally merchantable. Best productivity occurs where mineral[Pl] soils underlie relatively shallow (<30 cm) peaty horizons. Such sites may have

potential for mounding treatments to improve rooting zone aeration and nutrientregime. All species should be established on elevated (natural or artificial)microsites. Pl often shows best productivity in natural stands. SSLe 3-4 (0 onshallow veneers); burning difficult.

Cw Pl Yc, Generally no potential for timber production. Avoid disturbance.

Cw Yc Similar considerations to 11 above. Because swamp forests have some mineral(Hw Ss) seepage influence, they are generally more productive than bog forests (11). TheseHard: Dr sites are still only marginally productive, however, and any treatment must be

aimed at maintaining or improving microsite drainage/aeration.

Ss Shoreline forests are generally not merchantable. Such sites are more appropriately(Cw Hw Pl) managed for wildlife and aesthetic values. Avoid disturbance.

Cw Ss Marginally productive stands bordering estuaries. Avoid disturbance. If dis-Hard: Act Dr turbed, plant on elevated microsites. Such sites are more appropriately managed

for wildlife and aesthetic values.



CWHvh2

7 • 35

CWHvm1 Interpretations Tablea


01/06 Ba Slope stability. Root restrictions on LowCw 01b and 06b. Deep LFH (Mors) limit ES, FW

Hw nutrient availability on some sites.Ss

02 Cw Moisture and nutrient deficits. Root LowHw restrictions on shallow soils. Wind

Pl exposure.

03 Cw Moisture and nutrient deficits. Root MediumHw restrictions on shallow soils. Wind SA

Pl exposure.

04 Cw Slope stability. Root restrictions on MediumHw shallow veneers. Competing vegetation. RSBa

Ss

05 Ba Slope stability. Competing vegetation. HighCw RS, SB, FW

HwSs

08 Ba Slope stability. Competing vegetation. Very HighCw RS, SB, FW,

Hw FNSs

12 Cw Saturated, peaty soils restrict rooting, MediumHw nutrient availability, and productivity. SA, ES

Pl

13 Cw Saturated, peaty soils severely limit MediumHw rooting, nutrient availability, and SA

Pl productivity.

14 Cw Saturated, poorly aerated soils limit MediumHw rooting and productivity. SA, SB, FN

BaSs

a Refer to Section 7.2 for an explanation of each category in the table. Interpretations for activefluvial ecosystems (09, 10, 11) are presented on page 7•46 for all CWH subzones.

b Site index estimates are based on unpublished Ministry of Forests data; limited data for 04,12, and 13.


Silviculture

7• 36


Ba Cw Ba and Ss best suited to nutrient-medium sites that lack salal (i.e., richest examplesHwe Sse] of 01, often on base-rich bedrock). Cw may be favoured on unstable/windy slopesHard: Dr (rooting habit offers stability). These sites often occur on steep colluvial slopes

where mechanical disturbance should be minimized. There is often abundantadvance regeneration (mostly Hw) and natural regeneration of Hw can be ex-pected. SSLg 1-3 (on 01b)

Pl Marginal sites for timber production; avoid logging. SSL 0.[Cw Fdf Hw]

Cw Hw Often marginally merchantable. Avoid excessive disturbance, especially on 03b.[Fdf Pl] SSL 0.Hard: Dr

Ba Cw Risk of weevil damage on Ss. 04 occurs almost exclusively on steep, potentially[Hwe Sse] unstable colluvial slopes over base-rich bedrock. Mechanical disturbance shouldHard: Dr be minimized. There is often abundant advance and natural Hw regeneration, but

because these are nutrient-rich sites, Ba, Cw, (and Ss) should be managed for. Cwmay be favoured on unstable slopes (rooting habit offers stability). SSL 1-3 (on stable slopes with deep soils only).

Ba Cw Risk of weevil damage on Ss. 05 often occurs in a complex with 01 on slightly[Hwe Sse] moister and/or richer sites. Competing vegetation is a potential concern and sitesHard: Act Dr should be planted promptly. Minimize mineral soil exposure. SSL 2-4.

Ba Cw Hw should only be actively managed for on sites with thick (>20 cm) LFH. Risk[Hwe Sse] of weevil damage on Ss. These productive sites require careful planning to avoidHard: Act Dr degradation and brush problems. Log during driest season with minimal ground

disturbance. Dr will be quick to invade disturbed sites from adjacent stands;control seed sources (girdling, hack and squirt). Plant sites promptly with large,sturdy stock. Assess/control competing vegetation. SSL 3-4; successful burn maybe difficult to achieve.

Cw Hw Yc Bog forests are only marginally merchantable. All species must be established on[Pl] elevated (natural or artificial) microsites. Retain advance regeneration.(Hm)

Cw Pl Yc Generally no potential for timber production. Avoid disturbance.

Cw Highest productivity occurs on 14a where mineral seepage influence is greatest.(Hwe Sse) All species must be established on elevated microsites. Consider cluster planting

(see page 7•15) and reduced stocking. Avoid mechanical disturbance and destruc-tion of natural mounds. Preserve natural regeneration of all species.

d Species are in alphabetical order within primary, secondary [ ], and tertiary ( ) categories. e Risk of Porcupine damage, especially on Hw and Ss in the CWHvm1. f Fd restricted to Gardner Canal/ Kitlope area. g Slashburning severity levels (SSL) are described in Section 7.2.6, page 7•27.

CWHvm1

7 • 37

CWHvm2 Interpretations Tablea

Productivityb VegetationSite Site index - ht (m) at 50 yr Limiting factors for potential &series 0 10 20 30 40 productivity and regeneration complexes

01/06 Ba Slope stability. Root restrictions on 01b LowCw and 06b. Deep LFH (Mors) limit ES, FW

Hw nutrient availability on some sites. Wet,Ss heavy snow.

02 Hw Moisture and nutrient deficits. Root Lowrestrictions on shallow soils. Windexposure.

03 Hw Moisture and nutrient deficits. Root Mediumrestrictions on shallow soils. Wind SAexposure.

05 Ba Slope stability. Competing vegetation. HighCw Wet, heavy snow. RS, SB, FW

HwSs

08 Ba Slope stability. Competing vegetation. Very HighCw Wet, heavy snow. RS, SW FW,

Hw FNSs

09 Cw Saturated, peaty soils restrict rooting, MediumHw nutrient availability, and productivity. ES

Wet, heavy snow.

10 Cw Saturated, peaty soils severely limit MediumHw rooting, nutrient availability, and ES

productivity. Wet, heavy snow.

11 Cw Saturated, poorly aerated soils limit MediumHw rooting and productivity. Wet, heavy SB, FN

snow.

a Refer to Section 7.2 for an explanation of each category in the table. b Site index estimates are based on unpublished Ministry of Forests data collected in the

CWHvm1 and adjusted to reflect the lower productivity of the CWHvm2. c Vegetation potential and complexes are described in Section 7.2.4, page 7•18.

Silviculture

7• 38


Ba Ba and Ss best suited to nutrient-medium sites (i.e., richest examples of 01 and[CweHwf Ssf Yc] 06). Hw best suited to sites with thick (>20 cm) LFH. Cw may be favoured on(Hm) unstable/windy slopes (rooting habit offers stability). Hm restricted to upper

elevations. 01 often occurs on steep colluvial slopes where mechanical disturbanceshould be minimized. There is often abundant advance regeneration (Hw and Ba)and post-logging natural regeneration of Hw can be expected. Planting will berequired to increase component of other species. SSLg 1-3 (0 on 01b).

Pl These sites are very rare in the CWHvm2 of the PRFR. Marginal sites for timber [Cwe Hwf Yc] production; avoid logging.

Cwe Hwf These sites are very rare in the CWHvm2 of the PRFR. Often marginally[Pl Yc] merchantable. Avoid excessive disturbance.

Ba Cwe 05 often occurs in a complex with 01 on slightly moister and/or richer sites. Hm[Hwf Ssf Yc] restricted to upper elevations. Competing vegetation is a potential concern and(Hm) sites should be planted promptly. Minimize mineral soil exposure. SSL 2-4.

Ba Cwe Hw should only be promoted on sites with thick (>20 cm) LFH. Some risk of[Hwf Ssf Yc] weevil damage on Ss. These productive sites require careful planning to avoid

degradation and brush problems. Log during driest season with minimal grounddisturbance. Plant sites promptly with large, sturdy stock. Assess/control compet-ing vegetation. SSL 2-3; successful burn may be difficult to achieve.

Cwe Hwf Yc Bog forests are only marginally merchantable. All species must be established on[Hm] elevated microsites. Retain advance regeneration.(Pl)

Pl Yc Generally no potential for timber production. Avoid disturbance.[Hm]

Cc Yc Marginal sites for timber production. All species must be established on elevated(Hm Hwf Ssf) microsites. Hm restricted to upper elevations. Consider cluster planting (see page

7•15) and reduced stocking. Avoid mechanical disturbance and destruction ofnatural mounds. Retain advance regeneration of all species.


e Cw restricted to lower elevations in CWHvm2. f Risk of Porcupine damage, especially on Hw and Ss in the CWHvm2. g Slashburning severity levels (SSL) are described in Section 7.2.6, page 7•27.

CWHvm2

7 • 39

CWHwm Interpretations Tablea


01 Hw Slope stability. Root restrictions on 01b. Medium Ss Deep LFH (Mors) limit nutrient avail- ES, FW

ability on some sites.

02 Hw Slope stability. Moisture and nutrient LowSs deficits. Root restrictions on shallow ES

soils. Wind exposure.

03 Hw Slope stability. Competing vegetation. HighSs RS, SB, FW,

04 Hw Slope stability. Competing vegetation. Very HighSs RS, SB, FW,

FN

08 Hw Saturated, mineral soils and wet, peaty MediumSs LFH restrict rooting, nutrient availabil- ES

ity, and productivity. Cemented hori-zons also restrict rooting.

09 Hw Saturated, poorly aerated soils limit MediumSs rooting and productivity. SB, FN

10 Pl Saturated, peaty soils severely limit Mediumrooting, nutrient availability, and ESproductivity.


b Site index estimates are based on unpublished Ministry of Forests data; very limited data forthe CWHwm.


Silviculture

7• 40


Hwe Sse Ba and Ss best suited to moist, nutrient-medium sites (i.e., richest examples of 01).[Baf Cwf] Hw best suited to sites with thick (>20 cm) LFH or where cemented horizons(Hm Yc) occur. Cw may be favoured on unstable/windy slopes (rooting habit offers stabil-Hard: Dr ity). Hm and Yc should be considered at upper elevations or on cold air drainage

sites. 01 often occurs on steep colluvial slopes where mechanical disturbanceshould be minimized. There is often abundant advance regeneration of Hw (andSs) and natural regeneration of Hw can be expected. SSLg 1-4 (0 on 01b).

Hwe Pl Avoid mechanical disturbance on these steep, upper colluvial/bedrock slopes.[Cwf] Retain advance regeneration of all species. Hw best choice on acidic LFH over(Hm Sse) rock. SSL 0-1; burning generally unacceptable.Hard: Dr

Sse 03 often occurs in a complex with 01 on slightly moister and/or richer sites where[Baf Cwf Hwe] Ss, Ba, (and Cw) should be favoured. Hw will regenerate naturally. Yc can be(Yc) considered at high elevations. Competing vegetation is a potential concern andHard: Act Dr sites should be planted promptly. Minimize mineral soil exposure. SSL 2-4.

Sse Hw should only be promoted on sites with thick (>20 cm) LFH. These productive[Baf Cwf Hwe] sites require careful planning to avoid degradation and brush problems. Log during(Yc) driest season with minimal ground disturbance. Dr will be quick to invade dis-Hard: Act Dr turbed sites from adjacent stands; control seed sources (girdling, hack and squirt).

Plant sites promptly with large, sturdy stock. Assess/control competing vegetation.SSL 2-4; successful burn may be difficult to achieve.

Pl Yc These sites are only marginally merchantable. Avoid soil disturbance and drainage[Hwe Cwf] interruption. All species must be established on elevated microsites. Retain(Hm) advance regeneration of all species. These are cold, wet sites that will be slow to

regenerate.

Sse Marginal sites for timber production. All species must be established on elevated[Hwe Cwf Yc] microsites. Consider cluster planting (see page 7•15) and reduced stocking. AvoidHard: Act Dr mechanical disturbance and destruction of natural mounds. Retain advance

regeneration of all species.

Pl Yc Bog woodlands; generally no potential for timber production. Avoid[Cwf] disturbance.


e Risk of Porcupine damage, especially on Hw and Ss in the CWHwm.f Ba and Cw do not occur naturally throughout most of the CWHwm; their use should be

restricted to southern portions. g Slashburning severity levels (SSL) are described in Section 7.2.6, page 7•27.

CWHwm

7 • 41

CWHws1 Interpretations Tablea


01 Hw Moisture deficits on some sites (01b). LowBa Slope stability (some steep colluvial ES, FW

slopes). Deep LFH (Mors) limit nutrientavailability on some sites.

02 Hw Moisture and nutrient deficits. Root LowPl restrictions on shallow soils. Wind

exposure.

03 Hw Moisture and nutrient deficits. Root LowBa restrictions on shallow soils. Wind

exposure.

04 Hw Slope stability on some steep, colluvial HighBa slopes. Competing vegetation. Root RS, SB, FW

restrictions on some shallow soils.

05 Hw Some root restrictions in gleyed soils. MediumBa Deep LFH (Mors) often limit nutrient ES, RS, FW

availability.

06 Hw Slope stability. Competing vegetation. Very HighBa Some root restrictions in gleyed soils. RS, SB, FW,

Cw FNSs

10 Hw Saturated, peaty soils severely limit MediumPl rooting, nutrient availability, and ES

productivity.

11 Hw Saturated, poorly aerated soils limit MediumCw rooting and productivity. SB, FN


b site index estimates are based on unpublished Ministry of Forests data. c Vegetation potential and complexes are described in Section 7.2.4, page 7•18.

Silviculture

7• 42


Ba Ba and Sxs best suited to nutrient-medium, fresh to moist sites (i.e., richest[Cwe Hwe Pl Sxse] examples of 01). Risk of weevil damage on Sxs. Pl suited to 01b (glaciofluvialHard: Dr gravels). There is often abundant advance regeneration of Hw and Ba and this

should be protected; natural regeneration of Hw can be expected. Fill plant withCw, Ba, and Sxs. Mixed stands will lessen the impacts of Porcupine when standsreach pole-sapling stage. SSLf 1-3.

Pl Marginal sites for timber production; avoid logging. Promote natural regeneration[Cw Hwe] of Pl or plant Pl if seeding-in is inadequate.

Hw Pl Often marginally merchantable. Avoid excessive disturbance, especially on 03a.[Cw] LFH horizons important for moisture retention. Light surface disturbance willHard: Dr promote natural Pl regeneration. Plant Pl if necessary. SSL 1-3 on 03a; 0 on 03b.

Ba Cw Risk of weevil damage on Sxs. 04 often occurs in a complex with 01 on slightly[Hwe Sxse] moister and/or richer sites. Competing vegetation is a potential concern and sites(Pl) should be planted promptly. Advance Hw and Ba often present. Minimize mineralHard: Act Dr soil exposure. Avoid logging during wet season. SSL 2-4.

Ba Cw Ba and Sxs best suited to nutrient-medium sites (i.e., richest examples of 05). Risk[Hwe Sxse] of weevil damage on Sxs. Favour Hw if LFH layers are thick (>20 cm). There isHard: Dr often abundant advance regeneration of Hw and Ba and this should be protected;

natural regeneration of Hw can be expected. Fill plant with Cw, Ba, and Sxs. Mixed stands will lessen the impacts of Porcupine when stands reach pole-saplingstage. Excessive disturbance will promote alder invasion. SSL 2-4.

Ba Cw Hw should only be promoted on sites with thick (>20 cm) LFH. Risk of weevil[Hwe Sxse] damage on Sxs. These productive sites require careful planning to avoid degrada-Hard: Act Dr tion and brush problems. Log during driest season with minimal ground distur-

bance. Dr will be quick to invade disturbed sites from adjacent stands; control seedsources (girdling, hack and squirt). Plant sites promptly with large, sturdy stock.Assess/control competing vegetation. SSL 2-3; successful burn may be difficult toachieve.

Pl Bog woodlands; generally no potential for timber production. Avoid disturbance.Cw

Cw All species must be established on elevated microsites. Consider cluster planting[Sxse] (see page 7•15) and reduced stocking. Avoid mechanical disturbance and destruc-(Ba Hwe) tion of natural mounds. Retain advance regeneration and promote natural regen-Hard: Act Dr eration of all species. Some potential for creating artificial mounds.


e Risk of Porcupine damage, especially on Hw and Ss in the CWHws1. f Slashburning severity levels (SSL) are described in Section 7.2.6, page 7•27.

CWHws1

7 • 43

CWHws2 Interpretations Tablea


01 Hw Slope stability (some steep colluvial LowBa slopes). Deep LFH (Mors) limit nutrient ES, FW

availability on some sites. Wet, heavysnow.



04 Hw Slope stability on some steep, colluvial HighBa slopes. Competing vegetation. Root RS, SB, FW

restrictions on some shallow soils. Wet,heavy snow.

05 Hw Some root restrictions in gleyed soils. MediumBa Deep LFH (Mors) often limit nutrient ES, RS, FW

availability. Wet, heavy snow.

06 Hw Slope stability. Competing vegetation. Very HighBa Some root restrictions in gleyed soils. RS, SB, FW,

Wet, heavy snow. FN

10 Hw Saturated, peaty soils severely limit MediumPl rooting, nutrient availability, and ES

productivity.

11 Hw Saturated, poorly aerated soils limit MediumCw rooting and productivity. SB, FN


b Site index estimates are based on unpublished Ministry of Forests data collected in theCWHws l and adjusted to reflect the lower productivity of the CWHws2.


Silviculture

7• 44


Bae Ba and Sxs best suited to nutrient-medium, fresh to moist sites (i.e., richest[Blf Cwg Hwh Pl examples of 01). Pl suited to driest sites. Hm restricted to upper elevations. ThereSxsh] is often abundant advance regeneration of Hw and Ba and this should be protected;(Hm) natural regeneration of Hw can be expected. Fill plant with Ba, Sxs, and (Cw).Hard: Dr Mixed stands will lessen the impacts of Porcupine when stands reach pole-sapling

stage. SSLi 1-3 (0 on shallow soils over bedrock).

Pl These sites are very rare in the CWHws2 of the PRFR. Marginal sites for timber[Cwg Hwh] production; avoid logging. Promote natural regeneration of Pl or plant Pl if

seeding-in is inadequate. SSL 0.

Hwh Pl These sites are uncommon in the CWHws2 of the PRFR. Often marginally[Cwg] merchantable. Avoid excessive disturbance. LFH horizons are important forHard: Dr moisture retention. Light surface disturbance will promote natural Pl regeneration.

Plant Pl if necessary. SSL 0.

Bae 04 often occurs in a complex with 01 on slightly moister and/or richer sites. Hm[Cwg Blf Hwh restricted to upper elevations. Competing vegetation is a potential concern andSxsh] (Hm) sites should be planted promptly. Advance Hw and Ba often present. MinimizeHard: Act Dr mineral soil exposure. Avoid logging during wet season. SSL 2-3.

Bae Ba and Sxs best suited to nutrient-medium, sites (i.e., richest examples of 05).[Cwg Blf Hwh Favour Hw if LFH layers are thick (>20 cm). Hm restricted to upper elevations.Sxsh] There is often abundant advance regeneration of Hw and Ba and this should be(Hm) protected; natural regeneration of Hw can be expected. Fill plant with Ba, Sxs, andHard: Dr (Cw). Mixed stands will lessen the impacts of Porcupine when stands reach pole

sapling stage. SSL 2-4.

Bae Hw should only be promoted on sites with thick (>20 cm) LFH. Risk of weevil[Blf Cwg Hwh damage on Ss. These productive sites require careful planning to avoid degrada-Sxsh] tion and brush problems. Log during driest season with minimal ground distur-Hard: Act Dr bance. Plant sites promptly with large, sturdy stock. Assess/control competing

vegetation. SSL 2-4; successful burn may be difficult to achieve.

Pl Bog woodlands are rare in the CWHws2; generally no potential for timber produc-Cwg tion. Avoid disturbance.

Cwg Marginal sites for timber production (and uncommon in the CWHws2 of the[Sxsh] PRFR). All species must be established on elevated microsites. Consider cluster(Bae Hwh) planting (see page 7•15) and reduced stocking. Avoid mechanical disturbance andHard: Act Dr destruction of natural mounds. Retain advance regeneration and promote natural

regeneration of all species.


e Ba is less vigorous in the easternmost CWHws2. f Bl should be considered on cold air drainage sites. g Cw restricted to lower elevations in western portions of the CWHws2. h Risk of Porcupine damage, especially on Hw and Sxs in the CWHws2. i Slashburning severity levels (SSL) are described in Section 7.2.6, page 7•27.

CWHws2

7 • 45

CWH (fluvial) Interpretations Tablea


vh2/08 Ss High fluvial benches. Competing Very Highvegetation. High (but seasonally RS, SBfluctuating) water tables may restrictrooting. Moderate flooding/erosionhazard.

vml/09 Ss High fluvial benches. As above. Very HighCA, RS, SB

wm/05 Ss High fluvial benches. As above. Frost/ Very Highcold air in some upper valleys. CA, RS, SB

ws1, Sxs High fluvial benches. As above. Frost/ Very Highws2/07 cold air in some upper valleys CA, RS, SB

(CHWws2).

vh2/09 Ss Middle fluvial benches. Competing Very Highvegetation. High (seasonally fluctuat- RSing) water tables restrict rooting.Frequent (annual) flooding, deposi-tion/erosion.

vm1/10 Ss Middle fluvial benches. As above. Very HighCA

wm/06 Ss Middle fluvial benches. As above. Very HighFrost/cold air in some upper valleys. CA

ws1 Sxs Middle fluvial benches. As above. Very Highws2/08 Frost/cold air in some upper valleys CA

(CWHws2).

vh2/10 no information Low fluvial benches. High water Highvm1/11 tables restrict rooting. Frequent and CA, WIwm/07 prolonged annual flooding, often ofws1, high velocity. Annual deposition/ws2/09 erosion. Competing vegetation.

a Refer to Section 7.2 for an explanation of each category in the table. b Site index estimates are based on (very limited) unpublished Ministry of Forests data. c Vegetation potential and complexes are described in Section 7.2.4, page 7•18.

Silviculture

7• 46


Cw Ss High fluvial benches represent the most productive forested ecosystems in the[Ba] CWH zone. Very high vegetation potential, sensitive soils (erosion, compaction),(Hw) and high wildlife, fisheries, and water values necessitate extremely careful planningHard: Dr and operations on these sites. Refer to Chapter 6 and fisheries, forestry, and wildlife

guidelines for riparian ecosystem management. Harvesting should be carried outquickly during the driest season. Mechanical disturbance and mineral soil exposure

Ba Cc should be minimized. Fine-textured surface horizons should be protected. Decidu-[Ssef] ous seed trees should be controlled in advance of harvest if conifer regeneration is(Hwe) the objective. Intensive vegetation control will be required to establish conifersHard: Act Dr quickly and evenly (herbicides/manual treatments; repeated treatments). Secure

stock early and plant immediately with large, sturdy stock on the most raisedSse microsites. Consider cluster planting (see page 7•15) and reduced stocking to[Bag Cwg Hwe] facilitate spot treatment around seedlings (fewer, more intensively managed plantHard: Act Dr ing spots of 3 - 5 seedlings) while maintaining patches of understory for wildlife.

Riparian management guidelines favour partial cutting over clearcutting and thusBa Cw prescribed fire is generally impractical as a vegetation management tool (although it[Blh Sxsef] has been shown to be effective on fluvial sites in the CWHvm). Shade-tolerant Cw(Hwc) and Ba are viable alternatives to Ss/Sxs, considering weevil and Porcupine hazardHard: Act Dr and vegetation competition. Hardwood management should be considered on many

sites.

Ss Middle fluvial benches are also extremely productive and present many of the same[Ba Cw] concerns noted above for high fluvial benches. Establishment of coniferous planta-(Hw) tions on medium benches, however, is even more problematic due to more frequentHard: Dr surface flooding, and associated sediment erosion /deposition, and extreme compe-

tition from deciduous trees and shrubs. Uncertainty about longevity of mediumbench sites also makes conifer establishment a questionable investment. Most sites

[Ba Cw Ssef] should be managed as pure hardwood (Act/Dr) stands. Middle bench sites are oftenHard: Act Dr more appropriately managed for wildlife, watershed, and aesthetic values (see

Chapter 6).

[Bag Cwg Sse]Hard: Act Dr

[Ba Blh Cw Ssef]Hard: Act Dr

Sites not suitable Low bench sites are not suited to conifer establishment (or commercially viablefor conifers. hardwood establishment) due to the frequent and often high-velocity flooding andHard: Acti Dr resultant erosion /sediment deposition. Do not disturb low bench sites; they are

best managed for wildlife, watershed, and aesthetic values (see Chapter 6).


e Risk of Porcupine damage, especially on Hw, Ss, and Sxs. f Risk of weevil damage on Ss and Sxs. g Ba and Cw do not occur naturally throughout most of the CWHwm. Their use should be

restricted to southern portions.h Bl should be considered on cold air drainage sites.i Act is rare or absent in the CWHvh2.

CWH (fluvial)

7 • 47

ESSFmc Interpretations Tablea


01 Bl Cold soils. Moderately deep, long- LowSxw lasting snowpack. Root restrictions on ES, FW

01b. Frost/cold air.

02/03 BI Severe moisture and nutrient deficits. LowSxw Root restrictions on shallow soils.

04 Bl Cold soils. Moisture/nutrient deficits. LowSxw Root restrictions on some shallow soils.

Frost/cold air.

05/06 Bl Cold soils. Moderately deep, long- HighSxw lasting snowpack. Competing vegeta- MS, SH, FW

tion. Root restrictions on fine-texturedsoils. Frost/cold air.

07 Bl Cold soils. Moderately deep, long- Very HighSxw lasting snowpack. Root restrictions on MS, SH, FW,

fine-textured, wet soils. Competing WAvegetation. Frost/cold air.

08 Bl Very cold, wet soils. Deep and long- Mediumlasting snowpack. Frost/cold air. SH

09 Bl Saturated, cold soils with poor aeration MediumSxw and low nutrient status. Rooting WI

restricted by high water table. Frost/cold air ponding.

10 Bl Saturated, cold soils with poor aeration. HighSxw Rooting restricted by high water table. WA

Frost/cold air ponding. Competing vegetation.

a Refer to Section 7.2 for an explanation of each category in the table. b Site index estimates are based on Kayahara et al. (1993). In the ESSF, site index decreases

dramatically with increasing elevation. Estimates provided here are relevant to thelower-elevation (operable) ESSF.


Silviculture

7• 48


Bl Sxw Considering the severe environmental and biological constraints in the ESSFmc,[Pl] small clearcuts or partial cuts should be considered on all sites; advance regenera-

tion and residual trees of good form should be retained. Risk of snow damage onPl, especially at higher elevations. Conserve LFH for moisture/nutrient retention,especially on 01a. Soil temperature and natural regeneration can be enhanced bysome reduction/mixing of LFH and mineral soil exposure. Risk of soil compactionand windthrow in 01b. SSLe 1-2.

Pl Marginal sites for timber production; avoid logging. Conserve thin LFH for(Bl Sxw) moisture/nutrient retention. SSL 0.

Bl Pl Sxw Conserve LFH for moisture and nutrient retention. Some mechanical disturbance(summer logging) may be beneficial in improving soil temperature/nutrient regime(except on shallow soils over bedrock). Shallow soils and exposed locationssusceptible to windthrow. Marginally productive sites. SSL 0-1. See generalcomment on ESSFmc under 01 above.

Bl Sxw Pl is susceptible to snow damage and is also limited by shade intolerance on[Pl]S brushy sites. Plant sites promptly after harvest. Assess/treat competing vegetation.

Minimize mineral soil exposure. Medium-severity burn generally beneficial incontrolling vegetation and improving soil temperature. SSL 2-3. Fine-texturedsoils have higher risk of compaction and windthrow. See general comment onESSFmc under 01 above.

Bl Sxw Pl restricted by susceptibility to snow damage and shade intolerance. Plant sites (Pl) promptly with large, sturdy stock. Assess/control competing vegetation. Minimize

mineral soil exposure by patch scarifying to establish seedlings. Elevatedmicrosites generally preferred planting spots. SSL 2-4; medium-severity burn willgenerally be beneficial in improving soil temperature. High-severity burn requiredto (temporarily) control vegetation. Risk of compaction and windthrow. Seegeneral comment on ESSFmc under 01 above.

Bl Sxw These meadow forests are marginal for timber production. Regeneration will bedifficult on these high-elevation, snowy sites. Partial cut only to promote naturalregeneration. Retain advance regeneration.

Bl Sxw These sites are very marginal for timber production and should not be logged.High risk of frost damage on Sxw. Choose elevated microsites for planting.

Bl Sxw Sxw and Bl may be damaged by frost. Plant sites promptly with large, sturdy stock. Assess/control competing vegetation. Minimize mineral soil exposure bypatch scarifying or mounding to establish seedlings. Elevated microsites arepreferred planting spots (drainage, warmer soils, less frost). Consider clusterplanting (see page 7•15) and reduced stocking. Sites often have higher risk ofcompaction and windthrow (finer textures, high water tables). SSL 4-5. Seegeneral comment on ESSFmc under 01.

d Species are in alphabetical order within primary, secondary [ ],and tertiary ( ) categories. SeeSection 7.2.5, page 7•22. Tree species codes are described in Appendix 3.


ESSFmc

7 • 49

ESSFmk Interpretations Tablea


01 Bl Cold soils. Deep, long-lasting LowSxw snowpack. Root restrictions on 01b. ES, FW

Frost/cold air.

02/03 Bl Severe moisture and nutrient deficits. LowSxw Root restrictions on shallow soils over

bedrock.

04 Bl Cold soils. Long-lasting snowpack. HighSxw Competing vegetation. Root restrictions MS, SH

on fine-textured soils. Frost/cold air.

05 Bl Cold soils. Deep, long-lastingSxw snowpack. Root restrictions on fine- Very High

textured, wet soils. Competing vegeta- MS, SHtion. Frost/cold air.

06/07 Bl Saturated, cold soils with poor aeration. HighSxw Rooting restricted by high water table. WA

Frost/cold air ponding. Competingvegetation.

a Refer to Section 7.2 for an explanation of each category in the table. b There have been no site index data collected in the ESSFmk. Site index estimates are based

on Kayahara et al. (1993). In the ESSF, site index decreases dramatically with increasingelevation. Estimates provided here are relevant to the lower-elevation (potentially operable)ESSF.


Silviculture

7• 50


Bl Sxw Considering the severe environmental and biological constraints in the ESSFmk,[Pl] small clearcuts or partial cuts should be considered on all sites; advance regenera-(Baf Hm) tion and residual trees of good form should be retained. Risk of snow damage on

Pl. Conserve LFH for moisture/nutrient retention, especially on 01a. Soil tempera-ture and natural regeneration can be enhanced by some reduction/mixing of LFHand mineral soil exposure. Risk of soil compaction and windthrow in 01b.SSLg 1-2.

Pa Pl Marginal sites for timber production; avoid logging. Long term maintenance of Pa(Bl Hm Sxw) component in these stands is probably dependent on natural fire cycle.

Bl Sxw Pl is susceptible to snow damage and is also limited by shade intolerance on[Pl] brushy sites. Plant sites promptly after harvest. Assess/treat competing vegetation.(Baf Hm) Minimize mineral soil exposure. Medium-severity burn generally beneficial in

controlling vegetation and improving soil temperature. SSL 2-3. Fine-texturedsoils have higher risk of compaction and windthrow. See general comment onESSFmk under 01 above.

Bl Sxw Pl restricted by susceptibility to snow damage and shade intolerance. Plant sites(Baf Hm Pl) promptly with large, sturdy stock. Assess/control competing vegetation. Minimize

mineral soil exposure by patch scarifying to establish seedlings. Elevatedmicrosites generally preferred planting spots. SSL 2-3; medium-severity burn willgenerally be beneficial in improving soil temperature. High-severity burn requiredto control vegetation. See general comment on ESSFmk under 01 above.

Bl Sxw Sxw and Bl may be damaged by frost. Plant sites promptly with large, sturdystock. Assess/control competing vegetation. Minimize mineral soil exposure bypatch scarifying or mounding to establish seedlings. Elevated microsites arepreferred planting spots (drainage, warmer soils, less frost). Consider clusterplanting (see page 7•15) and reduced stocking. Sites often have higher risk ofcompaction and windthrow (finer textures, high water tables). SSL 3-4. Seegeneral comment on ESSFmk under 01 above.


e Logging has just begun in the ESSFmk. Comments are based on experience in the ESSFmc.The ESSFmk experiences more summer drought than the ESSFmc and has a wetter, deepersnowpack. Pa should be retained wherever it regenerates naturally; leave seed trees standingfor wildlife value and diversity.

f Ba occurs only in western ESSFmk. g Slashburning severity levels (SSL) are described in Section 7.2.6, page 7•27.

ESSFmk

7 • 51

ESSFwv Interpretations Tablea


01 Bl Cold soils. Deep, long-lasting LowSxw snowpack. Root restrictions on 01b. ES, FW

Frost/cold air.

02/03 Bl Severe moisture and nutrient deficits. LowSxw Root restrictions on shallow soils over

bedrock.

04 Bl Cold soils. Moisture/nutrient deficits. LowSxw Root restrictions on some shallow soils.

Frost/cold air.

05 Bl Cold soils. Deep, long-lasting HighSxw snowpack. Competing vegetation. Root MS, SH, FW

restrictions on fine-textured soils. Frost/cold air.

06 Bl Cold soils. Deep, long-lasting Very HighSxw snowpack. Root restrictions on fine- MS, SH, FW,

textured, wet soils. Competing vegeta- WAtion. Frost/cold air.

07 Bl Very cold, wet soils. Deep and long- Mediumlasting snowpack. Frost/cold air. SH

08 Bl Saturated, cold soils with poor aeration MediumSxw and low nutrient status. Rooting WI

restricted by high water table. Frost/cold air ponding.

09 Bl Saturated, cold soils with poor aeration. HighSxw Rooting restricted by high water table. WA

Frost/cold air ponding. Competingvegetation.

a Refer to Section 7.2 for an explanation of each category in the table.b There have been no site index data collected in the ESSFwv. Site index estimates are based

on Kayahara et al. (1993). In the ESSF, site index decreases dramatically with increasingelevation. Estimates provided here are relevant to the lower-elevation (operable) ESSF.


Silviculture

7• 52


Bl Sxw Considering the severe environmental and biological constraints in the ESSFwv,[Pl] small clearcuts or partial cuts should be considered on all sites; advance regenera-(Hm) tion and residual trees of good form should be retained. Risk of snow damage on Pl.

Conserve LFH for moisture/nutrient retention, especially on 01a. Soil temperatureand natural regeneration can be enhanced by some reduction/mixing of LFH andmineral soil exposure. Risk of soil compaction and windthrow in 01b. SSLe 1-2.

Pl Bl is a secondary species (not tertiary) in 03. Marginal sites for timber production;(Bl Hm Sxw) avoid logging. Conserve thin LFH for moisture/nutrient retention. SSL 0.

Pl Marginally productive sites. Conserve LFH for moisture and nutrient retention.[Bl] Some mechanical disturbance (summer logging) may be beneficial in improving(Hm Sxw) soil temperature/nutrient regime (except on shallow soils over bedrock). Shallow

soils and exposed locations susceptible to windthrow. Marginally productive sites.See general comment on ESSFwv under 01 above.

Bl Sxw Pl is susceptible to snow damage and is also limited by shade intolerance on brushy[Pl] sites. Plant sites promptly after harvest. Assess/treat competing vegetation. Mini-

mize mineral soil exposure. Medium-severity burn generally beneficial in control-ling vegetation and improving soil temperature. SSL 2-3. Fine-textured soils havehigher risk of compaction and windthrow. See general comment on ESSFwv under01 above.

Bl Sxw Pl severely restricted by susceptibility to snow damage and shade intolerance. Plant(Pl) sites promptly with large, sturdy stock. Assess/control competing vegetation.

Minimize mineral soil exposure by patch scarifying to establish seedlings. Elevatedmicrosites generally preferred planting spots. SSL 3-4; medium-severity burn willgenerally be beneficial in improving soil temperature. High-severity burn requiredto (temporarily) control vegetation. See general comment on ESSFwv under 01above.

Bl Sxw These meadow forests are marginal for timber production. Regeneration will bedifficult on these high-elevation, snowy sites. Partial cut only to promote naturalregeneration. Retain advance regeneration.

Bl Sxw These sites are very marginal for timber production and should not be logged.High risk of frost damage on Sxw. Choose elevated microsites for planting.

Bl Sxw Sxw and Bl may be damaged by frost. Plant sites promptly with large, sturdy stock.Assess/control competing vegetation. Minimize mineral soil exposure by patchscarifying or mounding to establish seedlings. Elevated microsites are preferredplanting spots (drainage, warmer soils, less frost). Consider cluster planting (seepage 7•15) and reduced stocking. Sites often have higher risk of compaction andwindthrow (finer textures, high water tables). SSL 4-5. See general comment onESSFwv under 01 above.



ESSFwv

7 • 53

ICHmc1/1a Interpretations Tablea


mc1/ Pl Moisture and nutrient deficits on 01b. Mediummc1a Sx Competing vegetation where there is a MH, ES,01 Hw deciduous component in the mature FW

stand.

mc1 Pl Severe moisture and nutrient deficits. Low02 Hw Root restrictions on shallow soils over

bedrock.

mc1a Pl Competing vegetation, especially where High02 Sx there is a deciduous component in the MH, MS,

mature stand. FW

mc1 Sx Competing vegetation, especially where High03 there is a deciduous component in the MH, MS,

mature stand. FW

mc1a Sx Competing vegetation. Root restrictions Very High03 on some fine-textured, gleyed soils. MH, MS,

Frost/cold air on some lower slope/ FNdepressions.

mc1 Sx Competing vegetation. Root restrictions Very High04 on some fine-textured, gleyed soils. MH, MS,

Frost/cold air on lower slopes. FN

mc1 Sx Competing vegetation. High (but Very High05 seasonally fluctuating) water tables may CW, MH,

restrict rooting. Frost/cold air. Risk of MSflooding/erosion.

mc1 Sx Saturated, cold soils with poor aeration Medium to High06 restrict rooting and productivity. Frost/ WA, (MS)

cold air.

a Refer to Section 7.2 for an explanation of each category in the table.b Site index estimates are based on unpublished Ministry of Forests data; very limited data for

the ICHmc1/1a.c Vegetation potential and complexes are described in Section 7.2.4, page 7•18.

Silviculture

7• 54


Hwe Pl Sx Ba in the ICHmc1a only, on nutrient-medium, moister sites (01a). Natural Hw best[Blf Ba] suited to unburned 01a with deeper LFH (>10 cm). Pl best choice on 01b. SomeHard: At Ep mixing of LFH with mineral soil may be beneficial. Avoid excessive mechanical

disturbance if At and Ep are present. SSLh 2-3 on 01a; SSL 0-2 on 01b. Fire maydegrade driest 01b.

PI Marginal sites for timber production; avoid logging. Conserve thin LFH for(Blf Hw) moisture and nutrient retention. SSL 0.Hard: At

Ba Sx Risk of spruce weevil; check local conditions and consider alternative species if[Hwe Pl] risk is high. Avoid excessive mechanical disturbance and logging during wetter(Cw eg) seasons in order to minimize competing vegetation, especially where At and EpHard: Act. At Ep are present. SSL 2-3; burning may be beneficial in temporarily controlling

competing vegetation. Burning may also improve productivity where LFHhorizons are thick (>15 cm).

Hwe Sx[Blf Pl]Hard: Act At Ep

Ba Sx Risk of spruce weevil; check local conditions and consider alternative species if[Hwe Pl] risk is high. Pl is limited by shade intolerance. These productive sites require(Cweg) careful planning to avoid degradation and brush problems. Log during winter orHard: Act At Ep during dry periods. Mechanical disturbance/site treatment should be avoided due

to potential for soil compaction, seepage surfacing, and increased vegetationSx competition. Plant sites promptly with large, sturdy stock. Plant on elevated[Blf Hwe Pl] microsites. Assess/control competing vegetation. SSL 2-4; successful burn may beHard: Act At Ep difficult to achieve on these wet, brushy sites.

Sx Risk of spruce weevil; check local conditions and consider alternative species if[Blf Pl] risk is high. Pl limited by shade intolerance on these brushy sites. Floodplain sitesHard: Act At Ep require careful planning to minimize compaction, erosion, and brush problems.

Winter log if possible. Coniferous regeneration will be slow to establish followingdisturbance due to very high vegetation competition. Vegetation control will berequired to establish conifers. Plant large, sturdy stock on elevated microsites.Consider cluster planting (see page 7•15) and reduced stocking. Hardwoodmanagement should be considered, especially on low and medium benchfloodplains. SSL 3-4; successful burn difficult to achieve. See Chapter 6 forwildlife habitat considerations in riparian areas.

Sx All species must be established on elevated microsites. Avoid mechanical distur-[Blf] bance and destruction of natural mounds. Retain advance regeneration of all(Hwe) species and fill plant on mounds (Sx). SSL 4-5 but difficult to achieve and de-Hard: Act stroys natural regeneration.

d Species are in alphabetical order within primary, secondary [ ] and tertiary ( ) categories. SeeSection 7.2.5, page 7•22. Tree species codes are described in Appendix 3.

e Risk of frost damage to Hw and Cw throughout the ICHmc 1/1 a. f Moose browse on Bl should be expected throughout the ICHmc1/1a. g Cw is rare in ICHmc1; use on trial basis only. h Slashburning severity levels (SSL) are described in Section 7.2.6, page 7•27.

ICHmc1/mc1a

7 • 55

ICHmc2 Interpretations Tablea


01 Pl Moisture and nutrient deficits on 01b. MediumSx Competing vegetation where there is a MH, FW

Hw deciduous component in the matureBl stand. Frost, especially in 01(2).

02 Pl Severe moisture and nutrient deficits. LowHw Root restrictions on shallow soils over

Sx bedrock.

03 Pl Competing vegetation, especially where HighSx there is a deciduous component in the MH, MS, FW

Hw mature stand.Ba

04/54 Pl Competing vegetation, especially where HighSx there is a deciduous component in the MH, MS, FW

Hw mature stand (54). Frost/cold air in 54.Bl

05 Pl Competing vegetation. Root restrictions Very HighSx on some fine-textured, gleyed soils. MH, MS, FN

Hw Frost/cold air on some lower slopes/Ba depressions.

06 Sx Competing vegetation. High (but Very Highseasonally fluctuating) water tables may CW, MH, MSrestrict rooting. Frost/cold air.

07 Sx Saturated, cold soils with poor aeration Highrestrict rooting and productivity. Frost/ WA, MScold air.

08 Pl Saturated, cold soils with poor aeration MediumSx restrict rooting and productivity. Frost/ WI

cold air.

51 Pl Moisture and nutrient deficits. Low

52/53 Pl Competing vegetation. Frost/cold air on High to VerySx lower slopes and valley bottoms, High

especially in the east. MH, AS, MS

a Refer to Section 7.2 for an explanation of each category in the table. b Site index estimates are based on unpublished Ministry of Forests data. Limited data for site series 02,

03, 06, 07, and 08.c Vegetation potential and complexes are described in Section 7.2.4, page 7•18.

Silviculture

7• 56


Hwe Pl Sx Pl (natural or planted) best choice on 01b; Sx on 01a. Cw should be considered on[Blf Cwe] moister examples of 01a. Natural Hw best suited to unburned 01a with deeperHard: At Ep LFH (>10 cm). Some mixing of LFH with mineral soil may be beneficial in 01a.

Avoid excessive mechanical disturbance if At and Ep are present. Frost may be aconcern in 01(2). SSLh 2-3 on 01a; SSL 0-2 on 01b. Fire may degrade driest 01b.

Pl Marginal sites for timber production; avoid logging. Conserve thin LFH for[Blf Hwe] moisture/nutrient retention. SSL 0.Hard: At

Cwe Hwe Sx Some risk of spruce weevil. Frost may hamper regeneration on low-lying sites.[Blf Pl] Avoid mechanical disturbance and logging during wetter seasons in order to(Bag) minimize competing vegetation and compaction of fine-textured soils. WinterHard: Act At Ep logging preferable, especially in 04. SSL 2-4; burning may be beneficial in

temporarily controlling competing vegetation and in improving site productivityCwe Sx where LFH is >15 cm.[Blf Hwe Pl](Bag)Hard: Act At Ep

Blf Cwe Sx Risk of spruce weevil. Pl is limited by shade intolerance. These productive sites[Hwe Pl] require careful planning to avoid degradation and brush problems. Log during(Bag) winter or dry periods. Plant sites promptly with large, sturdy stock. Plant onHard: Act At Ep elevated microsites. Assess/control competing vegetation. SSL 3-4 (difficult).

Cwe, Sx Risk of spruce weevil. Pl limited by shade intolerance. Floodplain sites require[Blf Pl] careful planning to avoid Compaction, erosion, and brush problems. Winter log if(Hwe) possible. Vegetation control required to establish conifers. Plant large, sturdy stockHard: Act At Ep on elevated microsites. Consider cluster planting (see page 7•15) and reduced

stocking. Consider hardwood management. SSL 3-4 (but often impractical). SeeChapter 6 for wildlife habitat considerations in riparian areas .

Sx All species must be established on elevated microsites. Avoid mechanical distur-[Blf Cwe] bance and destruction of natural mounds. Retain advance regeneration of all(Hwe Pl) species and fill plant on mounds Sx. SSL 4-5 (often impractical).Hard: Act At Ep

Pl Sb Sx Marginal sites for timber production; avoid logging. Risk of frost damage on Sx.Choose elevated microsites for planting.

Pl Bl and Sx should only be considered on moister microsites. Shallow LFH and[Blf Sx] coarse textures generally preclude burning or mechanical disturbance. Promote(Hwe) natural Pl regeneration. SSL 0-1.

Pl Sx Depending on coniferous/deciduous component, these seral stands often have[Blf Cwe Hwe] limited timber values at present. Conversion to coniferous stands can be veryHard: Act At Ep costly due to vigorous hardwood/shrub regeneration following disturbance.

d Species are in alphabetical order within primary, secondary [ ], and tertiary ( ) categories. e Risk of frost damage on Hw and Cw. f Moose browse on Bl should be expected. g Ba in upper elevations in western ICHmc2 only. h Slashburning severity levels (SSL) are described in Section 7.2.6, page 7•27.

ICHmc2

7 • 57

ICHvc Interpretations Tablea


01 Hw Heavy and long-lasting snowpack. HighBl Competing vegetation. Frost and cold MS, ES, FWSx air, specially on 01(2).

02 Hw Heavy and long-lasting snowpack. LowBl (although less so than in 01). Moisture ES

and nutrient deficits on upper slopes/ridgecrests. Root restrictions on shallowsoils over bedrock. Frost/cold air in02(2).

03 Bl Heavy and long-lasting snowpack. Very HighSx Competing vegetation. Frost/cold air, MS, FW

especially in 03a. Root restrictions insome gleyed soils (03b).

04 Bl Competing vegetation. High (but Very HighSx seasonally fluctuating) water tables may CW, MS

restrict rooting. Frost/cold air. Risk oferosion.

05 Bl Competing vegetation. High (but Very HighSx seasonally fluctuating) water tables may CW, MS

restrict rooting. Frost/cold air. Risk offlooding/erosion.

06 Bl Saturated, cold soils with poor aeration HighSx restrict rooting and productivity. Frost/ WA, WI

cold air.

51 Very heavy and long-lasting snowpack; Very Highsnowslides. Competing vegetation. WA, BNFrost/cold air.

52 Very heavy and long-lasting snowpack. Very HighCompeting vegetation. Frost/cold air. WA, WIRooting restricted by permanently highwater table.

a Refer to Section 7.2 for an explanation of each category in the table. b Site index estimates are based on unpublished Ministry of Forests data; very limited data for

the ICHvc. c Vegetation potential and complexes are described in Section 7.2.4, page 7•18.

Silviculture

7• 58


Bl Hw should only be used in 01(1) where cold air ponding is not a concern. Finer[Hwe Sxf] textured, moister soils are associated with 01(2); avoid excessive disturbance to(Hm) minimize compaction and vegetation competition (consider winter logging). SSLg

Hard: Act At Ep 2-3; fire may be beneficial where LFH >15 cm, but destroys advance Bl and Hwregeneration.

Bl Hwe Pl should only be considered on the driest upper slopes and ridges or coarse[Pl Sxf] outwash; it is rare in the ICHvc; probably limited by the deep snowpack. Hw only(Hm) on 02(1). 02 includes some sites with shallow soils and thin LFH; avoid distur-Hard: At Ep bance on these sites (fire or mechanical). Otherwise, some mixing of LFH may be

beneficial. Advance Bl and Hw regeneration may be acceptable.SSL 0-2.

Bl These productive sites require careful planning to avoid degradation and brush[Sxf] problems. Log during winter or dry periods. Plant sites promptly with large, sturdyHard: Act At Ep stock. Advanced Bl may be acceptable. Assess/control competing vegetation. SSL

3-4; successful burn may be difficult to achieve.

Bl Floodplain sites require careful planning to avoid compaction, erosion, and brush[Sxf] problems. Winter log if possible. Vegetation control will be required to establishHard: Act At conifers. Plant large, sturdy stock on elevated microsites especially in 05. Consider

cluster planting (see page 7•15) and reduced stocking. Hardwood managementshould be considered, especially on low and medium bench sites (05). SSL 3-4.Riparian management guidelines favour partial cutting over clearcutting and thus

Bl prescribed fire is generally impractical as a vegetation management tool. Refer to[Sxf] Chapter 6 and fisheries, forestry, and wildlife guidelines for riparian ecosystemHard: Act At management.

Bl All species must be established on elevated microsites. Consider cluster planting[Sxf] (see page 7•15) and reduced stocking. Avoid mechanical disturbance and destruc-Hard: Act At Ep tion of natural mounds. Retain advance regeneration of all species.

Bl Non-forested and generally not considered for treatment unless included within a[Sxf] cutblock. Mechanical clearing, herbicides, or burning required to establish coni-

fers. Soils are highly productive. Must be planted promptly if cleared.

(Bl Sxf) Generally no potential for timber production. Avoid disturbance.


e Risk of frost damage on Hw, especially in lower slope/valley bottoms where cold air/frostponds.

f Risk of snow damage and spruce weevil attack on Sx throughout the ICHvc. g Slashburning severity levels (SSL) are described in Section 7.2.6, page 7•27.

ICHvc

7 • 59

ICHwc Interpretations Tablea


01 Hw Competing vegetation, especially where MediumSx there is a deciduous component in MH, ES, FW

Bl mature stands [Bob Quinn phaseICHwc(a)]. Frost/cold air at lowerelevations [also ICHmc(a)].

02 Pl Severe moisture and nutrient deficits. LowHw Root restrictions on shallow soils over

bedrock.

03 Hw Moisture and nutrient deficits. Root MediumSx restrictions on some sites that are MH, ES

Pl shallow to bedrock. Competition fromBl At and Ep in seral stands.

04 Hw Competing vegetation. Frost/cold air on HighSx some valley-bottom sites. MH, MS,

Bl FW

05 Hw Competing vegetation. Frost/cold air on Very HighSx some valley-bottom sites. Root restric- MH, MS,

Bl tions on some gleyed soils. FW

06 Sx Competing vegetation. High (but Very HighBl seasonally fluctuating) water tables may CW, MS

restrict rooting. Frost/cold air. Risk offlooding/erosion.

07 Hw Cold, saturated soils with low nutrient HighSx status. Frost/cold air. Competing WA, WIBl vegetation.

08 Hw Saturated, cold soils with poor aeration Very High Sx restrict rooting and productivity. Frost/ WA, WI

Bl cold air.

a Refer to Section 7.2 for an explanation of each category in the table. b Site index estimates are based on unpublished Ministry of Forests data. c Vegetation potential and complexes are described in Section 7.2.4, page 7•18.

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7• 60


Bl Hwe Sx Hw appears to be limited by frost/cold air in the Bob Quinn phase; Pl and Sx are[Pl] more prevalent there. There is potential for natural/advance Hw and Bl regenera-Hard: At Ep Act tion on unburned sites. Some mixing of LFH with mineral soil may be beneficial,

but avoid excessive disturbance where At or Ep are present in mature stands.SSLf 2-3.

Pl Marginal sites for timber production; avoid logging. Conserve thin LFH for(Hwe) moisture/nutrient retention. SSL 0.Hard: At

Bl Hwe Pl Sx Sx can be favoured on moister microsites. Conserve limited LFH for moisture/Hard: At Ep nutrient retention. Avoid excessive disturbance in stands with At and Ep compo-

nent. SSL 0-2.

Bl Sx Sx uncommon in natural stands. Sites should be planted promptly to avoid need for[Pl Hwe] vegetation control. Minimize mineral soil exposure. Burning may be beneficial inHard: Act At Ep temporarily controlling vegetation (except fireweed). SSL 2-3.

Bl Sx These productive sites require careful planning to avoid degradation and brush[Hw’] problems. Log during winter or dry periods. Plant sites promptly with large, sturdyHard: Act At Ep stock. Assess/control competing vegetation. SSL 2-3; successful burn may be

difficult to achieve.

Bl Sx Floodplain sites require careful planning to avoid compaction, erosion, and brush(Hwe) problems. Winter log if possible. Vegetation control will be required to establishHard: Act At Ep conifers. Plant large, sturdy stock on elevated microsites; Consider cluster planting

(see page 7•15) and reduced stocking. Hardwood management should be consid-ered, especially on low and medium bench sites. SSL 3-4. Riparian managementguidelines favour partial cutting over clearcutting and thus prescribed fire isgenerally impractical as a vegetation management tool. See Chapter 6 for wildlifehabitat considerations in riparian areas.

Sx Marginal sites for timber production; avoid logging. High risk of frost damage on[Pl Bl] Sx, Bl, and Hw. Choose elevated microsites for planting. Retain advance regenera-

tion.

Bl Sx All species must be established on elevated microsites. Consider cluster planting(Hwe) (see page 7•15) and reduced stocking. Avoid mechanical disturbance and destruc-Hard: Act Ep tion of natural mounds. Retain advance regeneration of all species.


e Risk of frost damage on Hw throughout ICHwc; Hw of limited occurrence in the Bob Quinnphase.

f Slashburning severity levels (SSL) are described in Section 7.2.6, page 7•27.

ICHwc

7 • 61

MHmm1 Interpretations Tablea


01/04 Hm Cold soils. Frost/cold air. Heavy, long- MediumBa lasting snowpack. Thick, compacted ES

Yc LFH (Mor) limits nutrient availability.

02 Hm Cold soils. Frost/cold air. Heavy, long- LowBa lasting snowpack. Thick, compacted ES

Yc LFH (Mor) limits nutrient availability.Severe exposure to wind. Root restric-tions.

03 Hm Cold soils. Frost/cold air. Heavy, long- HighBa lasting snowpack. Competing vegeta- ES, SH

Yc tion.

05 Hm Cold soils. Frost/cold air. Heavy, long- HighBa lasting snowpack. Competing vegeta- ES, SH, SB

Yc tion.

06 Hm Cold, saturated soils. Heavy and very MediumBa long-lasting snowpack. Frost/cold air. SHYc

07 Hm Cold, saturated soils. Heavy and very HighBa long-lasting snowpack. Frost/cold air. SHYc Competing vegetation.

08 Hm Cold, saturated, peaty soils. Heavy and MediumYc very long-lasting snowpack. Frost/cold ES

air.

09 Hm Cold saturated mineral soils. Heavy and High Yc very long-lasting snowpack. Frost/cold SH, SB

air. Competing vegetation.

a Refer to Section 7.2 for an explanation of each category in the table.b No site index sampling has been carried out in the MH zone. Site index estimates are very

preliminary, based on Krajina (1969) and adjusted estimates from neighbouring zones. c Vegetation potential and complexes are described in Section 7.2.4, page 7•18.

Silviculture

7• 62


Ba Hm Yc To date there has been little or no development in the MH zone of the PRFR andmost of the zone is inaccessible due to steep terrain. Our silvicultural knowledgeof the MH zone is thus very limited and based mainly on (limited) experience inthe Vancouver Forest Region (Klinka et al. 1992).

Hm Yc Any development in this climatically and topographically extreme subalpine[Ba] zone should be done cautiously and conservatively, considering the biological

and environmental constraints to regeneration and forest productivity.

Important reforestation considerations include:

Ba Hm Yc • Harvesting should only occur on the most productive sites (MHmm1/01,/03 /04, /05) at lower elevations. Harvesting of site series 02 and 06 to 09should be considered as timber mining.

Ba Yc[Hm] • Harvesting should be restricted to small clearcuts (patch cuts) or partial

cuts in order to promote and protect natural/advance regeneration.

Hm Yc • Advance regeneration of most tree species (Ba, Hm,Yc) is generally(Ba) present in mature stands, and should be retained in anticipation of

release.

Ba Yc[Hm] • Natural regeneration of all species should be promoted through careful

planning of cutblock shape/size and providing for some (but not severe)surface disturbance of LFH horizons.

Hm Yc• Planting will be required on many sites to supplement natural regenera-

tion and careful attention must be paid to microsite (soil drainage, frostand wind exposure, aspect, protection from snowcreep, disturbed forest

Yc floors). Ba and Yc should be promoted in planting programs.[Hm]

• Slashburning is considered inappropriate on the majority of sites due tothe adverse impact on natural regeneration by seed and the destruction ofadvance regeneration.

• The most productive sites are moderate to steep colluvial slopes that areinfluenced by subsurface (flowing) seepage, but are freely drainedMHmm1/03 and /05). Productivity declines on imperfectly to poorlydrained sites. Disturbance of drainage or subsurface seepage flow willdecrease productivity.

• On most sites it will not be feasible to reach free-to-grow status for 20 ormore years and rotations will be very long (150 - 200 years).


MHmm1

7 • 63

MHmm2 Interpretations Tablea


01/04 Hm Cold soils. Frost/cold air. Heavy, long- MediumBa lasting snowpack. Thick, compacted ES

LFH (Mor) limits nutrient availability.

02 Hm Cold soils. Frost/cold air. Heavy, long- LowBa lasting snowpack. Thick, compacted ES

LFH (Mor) limits nutrient availability.Severe exposure to wind. Root restric-tions.

03 Hm Cold soils. Frost/cold air. Heavy, long- HighBa lasting snowpack. Competing vegeta- ES, SH

tion.


tion.

06 Hm Cold, saturated soils. Heavy and very MediumBa long-lasting snowpack. Frost/cold air. SH

07 Hm Cold, saturated soils. Heavy and very HighBa long-lasting snowpack. Frost/cold air. SH

Competing vegetation.

08 Hm Cold, saturated, peaty soils. Heavy and Mediumvery long-lasting snowpack. Frost/cold ESair.

09 Hm Cold saturated mineral soils. Heavy and High very long-lasting snowpack. Frost/cold SH, SB air. Competing vegetation.



Silviculture

7• 64


Ba Hm To date there has been little or no development in the MH zone of the PRFR and[Yce Blf] most of the zone is inaccessible due to steep terrain. Our silvicultural knowledge

of the MH zone is thus very limited and based mainly on (limited) experience inthe Vancouver Forest Region (Klinka et al. 1992).

Hm Any development in this climatically and topographically extreme subalpine[Ba Yce Blf] zone should be done cautiously and conservatively, considering the biological



Ba Hm • Harvesting should only occur on the most productive sites (MHmm2/01,[Yce BIf] /03, /04, /05) at lower elevations. Harvesting of site series 02 and 06 to 09

should be considered as timber mining.

Ba[Hm Yce Blf] • Harvesting should be restricted to small clearcuts (patch cuts) or partial


Hm • Advance regeneration of most tree species (Ba, Hm) is generally[Yce] present in mature stands, and should be retained in anticipation of(Ba Blf) release.

Ba Yc[Hm Yce Blf] • Natural regeneration of all species should be promoted through careful


Hm[Yce] • Planting will be required on many sites to supplement natural regenera-


Hm floors). Ba and Yc should be promoted in planting programs.[Yce]

• Slashburning is considered inappropriate on most sites due to the adverseimpact on natural regeneration by seed and the destruction of advanceregeneration.

• The most productive sites are moderate to steep colluvial slopes that areinfluenced by subsurface (flowing) seepage, but are freely drained(MHmm2/03 and /05). Productivity declines on imperfectly to poorlydrained sites. Disturbance of drainage or subsurface seepage flow willdecrease productivity.



e Yc is restricted to western portion of MHmm2.

f Bl is suitable in eastern portions of the MHmm2.

MHmm2

7 • 65

MHwh1 Interpretations Tablea


01 Hm Cold soils. Frost/cold air. Heavy, long- MediumBa lasting snowpack. Thick, compacted ES

Yc LFH (Mor) limits nutrient availability.

02 Hm Cold soils. Frost/cold air. Heavy, long- LowBa lasting snowpack. Thick, compacted ESYc LFH (Mor) limits nutrient availability.

Severe exposure to wind. Root restric-tions.

04 Hm Cold soils. Frost/cold air. Heavy, long- MediumBa lasting snowpack. ES, SH

Yc


Yc tion.

06 Hm Cold, saturated soils. Heavy and very MediumBa long-lasting snowpack. Frost/cold air. SHYc

07 Hm Cold, saturated soils. Heavy and very HighBa long-lasting snowpack. Frost/cold air. SHYc Competing vegetation.

08 Hm Cold, saturated, peaty soils. Heavy and MediumYc very long-lasting snowpack. Frost/cold ES

air.

09 Yc Cold saturated mineral soils. Heavy and HighHm very long-lasting snowpack. Frost/cold SH, SB

air. Competing vegetation.



Silviculture

7• 66


Ba Hm Yc To date there has been little or no development in the MH zone of the PRFR and[Cwe Hwe Sse] most of the zone is inaccessible due to steep terrain. Our silvicultural knowledge

of the MH zone is thus very limited and based mainly on (limited) experience inthe Vancouver Forest Region (Klinka et al. 1992).

Hm Yc Any development in this climatically and topographically extreme subalpine[Cwe] zone should be done cautiously and conservatively, considering the biological



Hm Yc • Harvesting should only occur on the most productive sites (MHwh1/01,[Ba Cwe Hwe] /04, /05) at lower elevations. Harvesting of site series 02 and 06 to 09

should be considered as timber mining.

Ba Yc[Cwe Hm Hwe Sse] • Harvesting should be restricted to small clearcuts (patch cuts) or partial


Hm Yc • Advance regeneration of most tree species (Ba, Hm, Yc) is generally(Ba) present in mature stands, and should be retained in anticipation of

release.

Ba Yc[Cwe Hm Sse] • Natural regeneration of all species should be promoted through careful


Hm Yc• Planting will be required on many sites to supplement natural regenera-


Yc floors). Ba and Yc should be promoted in planting programs.[Cwe](Hm Sse)

• Slashburning is considered inappropriate on the majority of sites due tothe adverse impact on natural regeneration by seed and the destruction ofadvance regeneration.

• The most productive sites are moderate to steep colluvial slopes that areinfluenced by subsurface (flowing) seepage, but are freely drained(MHwh1/05). Productivity declines on imperfectly to poorly drained sites.Disturbance of drainage or subsurface seepage flow willdecrease productivity.



e In lower elevations of the MHwh2 only.

MHwh1

7 • 67

SBPSmc Interpretations Tablea


01 Pl Cold soils. Moisture and nutrient LowSx deficits, especially on 01b. Root

restrictions on compacted tills.

02 Pl Severe moisture and nutrient deficits. LowSx

03 Pl Cold soils. Moisture and nutrient LowSx deficits. Root restrictions on compacted

tills.

04 Pl Very cold soils with high water tables. Medium Sx Nutrient deficits. Frost/cold air. Rooting WI

restricted by high water tables.

05 Pl Very cold soils with seasonally fluctu- HighSx ating water tables. Frost/cold air. WA, WI,

Rooting restricted by high water tables. RGCompeting vegetation.

06 Pl Very cold, wet, poorly aerated soils. HighSx Frost/cold air. Rooting restricted by WA, WI,

high water table. Competing vegetation. RG

07 Pl Very cold, saturated, poorly aerated MediumSx soils. Frost/cold air. Tree productivity WI

severely limited.

a Refer to Section 7.2 for an explanation of each category in the table. b Site index estimates are based on Wang et al. [1992], McLennan (1989), and unpublished

Ministry of Forests data. c Vegetation potential and complexes are described in Section 7.2.4, page 7•18.

Silviculture

7• 68


Pl Sxw should only be considered on the mesic phase (01a) Conservation of LFH(Sb Sxw) critical for moisture/nutrient retention; some surface disturbance (summer logging)Hard: At beneficial for natural Pl regeneration and increasing soil temperature. SSLe 0-1;

avoid burning, especially on 01b.

Pl (Sb Sxw) Marginal sites for timber production; avoid logging. Conserve thin LFH forHard: At moisture/nutrient retention. SSL 0.

Pl Marginal sites for timber production. Although moisture deficits occur during(Sb Sxw) summer, soils can be wet and prone to compaction in the spring. Some reductionHard: At of LFH horizons (mechanical site preparation [MSP] or fire) will improve soil

temperature and promote natural Pl regeneration. SSL 1-3.

Pl Sb Sxw Marginal sites for timber production. Sxw may be damaged by frost. Harvestduring winter or summer dry periods. Sites should be planted with Pl, with somenatural Sxw expected. SSL 1-3.

Sxw Sxw may be damaged by frost. Pl limited by shade intolerance and high water[Pl] tables, especially in 06. Plant sites promptly with large, sturdy stock. Plant onHard: Act elevated microsites (drainage, warmer soils, less frost). Consider cluster planting

(see page 7•15) and reduced stocking. Assess/control competing vegetation. Sitesoften have a high risk of compaction and windthrow (especially 06; finer textures,

Sxw high water tables) and surface erosion (especially 05; fluvial sites). Harvest during[Pl] winter or summer dry periods. SSL 3-5; burning difficult.Hard: Act

Pl Sb Sxw These sites are very marginal for timber production and should not be logged.High risk of frost damage on Sxw. Choose elevated microsites for planting.



SBPSmc

7 • 69

SBSdk Interpretations Tablea


01 Pl Cold soils. Moisture and nutrient MediumSxw deficits on some sites. Root restrictions Ms, AS, FW

on compacted tills 01a.

02/03 Pl Severe moisture and nutrient deficits. LowSxw Root restrictions on shallow soils over

bedrock.

04 Pl Moisture deficits. Root restrictions on Lowshallow soils over rock.

05 Pl Cold soils. Moisture and nutrient LowSxw deficits. Some root restrictions on finer-

textured, compacted tills.

06 Pl Cold soils. Root restrictions on fine- HighSxw textured soils. Competing vegetation. AS, FW, MH,

MS

07 Pl Very cold, wet, poorly aerated soils Very HighSxw (especially 07b). Frost/cold air. Rooting CW, WA

restricted by high water table and finetextures (07b). Competing vegetation.

08 Pl High (but fluctuating) water tables. Very HighSxw Frost/cold air. Competing vegetation. CW, WA

09/10 Pl Saturated, cold soils with poor aeration. Medium Sxw Rooting restricted by high water table. WL

Sb Frost and cold air ponding.

a Refer to Section 7.2 for an explanation of each category in the table.b Site index estimates are based on Wang et al. [1992], McLennan (1989), and unpublished

Ministry of Forests data. c Vegetation potential and complexes are described in Section 7.2.4, page 7•18.

Silviculture

7• 70


Pl Sxw Fd on south aspects only (trial basis, see footnote). Natural regeneration of Pl will[Fde] require mineral soil exposure. Mineral soil exposure will also enhance soil tem-Hard: At Ep perature, but conserve LFH, especially on 01b. SSLf 1-3. 01a has higher risk of

soil compaction and windthrow; log during winter or dry periods and choosecutblock boundaries carefully.

Pl Sb minor species on 03 only. Marginal sites for timber production; avoid logging.(Sxw Sb) Conserve thin LFH for moisture/nutrient retention. SSL 0.Hard: At Ep

Fde Pl Conserve organic matter on these warm, south aspects for moisture/nutrient(Sxw) retention. Mechanical preparation (drag scarification) preferable over burning forHard: At Ep promoting natural regeneration. Avoid excessive disturbance. Partial cutting

(shelterwood, seed tree) appropriate for regeneration of Fd.

Pl Sxw Sx restricted to moister microsites. Potential for compaction on fine-textured[Fde] Luvisols. Mechanical preparation (drag scarification) preferable over burning forHard: At Ep promoting natural regeneration while conserving LFH (moisture and nutrients).

Pl Sxw Plant sites promptly after harvest. Minimize mineral soil exposure especiallyHard: Act At Ep where At and Ep are present. Sites should be logged in winter or during dry

periods to avoid compaction and excessive disturbance. SSL 2-3; advance regen-eration often acceptable and thus burning may not be appropriate.

Sxw Pl is limited by shade intolerance and saturated soils. Sxw may be damaged by[Pl] frost. Plant sites promptly with large, sturdy stock. Assess/control competingHard: Act At Ep vegetation. Minimize mineral soil exposure by patch scarifying (07a) or mounding

(07b) to establish seedlings. Elevated microsites preferred planting spots (drain-age, cold soils, frost). Consider cluster planting (see page 7•15) and reducedstocking. Sites often have higher risk of compaction and windthrow (finer textures,high water tables) and surface erosion (fluvial sites). SSL 3-4 (3 on 07a).

Sxw Sx may be damaged by frost. Pl limited by shade intolerance and flooding/high[Pl] water tables. Floodplain sites require careful planning to avoid compaction,Hard: Act Ep erosion, and brush problems. Winter log if possible. Vegetation control will be

required to establish conifers. Plant large, sturdy stock on elevated microsites.Consider cluster planting (see page 7•15) and reduced stocking. Consider Actmanagement. SSL 3-4; partial cutting should be considered on riparian sites andthus burning may be impractical. See Chapter 6 for wildlife habitat considerationsin riparian areas.

Pl Sb Sxw Sxw on 10 only. These sites are very marginal for timber production and shouldnot be logged. High risk of frost damage on Sxw. Choose elevated microsites forplanting.


e Fd only occurs in eastern extremity of region. f Slashburning severity levels (SSL) are described in Section 7.2.6, page 7•27.

SBSdk

7 • 71

SBSmc2 Interpretations Tablea


01 Bl Cold soils. Moisture and nutrient LowPl deficits especially on (01c). Root AS, FW

Sx restrictions on compacted tills (01a).

02 Bl Severe moisture and nutrient deficits. LowPl Root restrictions on shallow soils over

Sx bedrock.Sb

03 Bl Very cold soils (cool aspects). Nutrient LowPl and (on some sites) moisture deficits.

Sx Root restrictions on fine-textured soils.Sb

05/06 Bl Cold soils (especially 06). Root HighPl restrictions on fine-textured soils. AS, MS, FW

Sx Competing vegetation.

07 Pl Very cold, wet soils. Nutrient deficits. LowSx Frost/cold air. Root restrictions due to WI, WA

high water table.

09 Bl Cold soils. Root restrictions on fine Very HighPl textured soils. Competing vegetation. MS

Sx

10 Bl Very cold, wet, poorly aerated soils Very HighPl (especially 10b). Frost/cold air. CW, WA

Sx Rooting restricted by high water tableand fine textures (10b). Competingvegetation.

12 Pl Saturated, cold soils with poor aeration. Medium Sx Rooting restricted by high water table. WI

Sb Frost and cold air ponding.

a Refer to Section 7.2 for an explanation of each category in the table.b Site index estimates are based on Wang et al. [1992], McLennan (1989), and unpublished

Ministry of Forests data; very limited data for Sb and Bl.c Vegetation potential and complexes are described in Section 7.2.4, page 7•18.

Silviculture

7• 72


Pl Sxw Pl should generally be favoured over Sxw on 01c. Conserve LFH for moisture/[Ble] nutrient retention, especially on 01c. Soil temperature and natural regeneration canHard: At be enhanced by some reduction of LFH and mineral soil mixing/incorporation. 01a

has higher risk of soil compaction and windthrow. SSLf 1-3.

Pl Marginal sites for timber production; avoid logging. Conserve thin LFH for(Ble Sxw) moisture/nutrient retention. SSL 0.Hard: At

Pl Reduction of LFH (or mixing with mineral soil) will generally improve soil tem-(Ble Sb Sxw) perature and productivity. Fine-textured soils have higher risk of compaction andHard: At windthrow. SSL 2-3.

Pl Sxw Plant sites promptly after harvest. Assess/treat competing vegetation. Minimize[Ble] mineral soil exposure. Medium-severity burn generally beneficial in controllingHard: Act At vegetation and improving soil temperature (SSL 2-4). Fine-textured soils have

higher risk of compaction and windthrow.

Pl Sb Sxw Regeneration will be very slow on these marginal sites. Mounding (on finer-Hard: At textured soils) to improve drainage and increase soil and air temperature may

improve productivity. SSL 4-5.

Sx Pl is limited by shade intolerance. Plant sites promptly with large, sturdy stock.[Ble Pl] Assess/control competing vegetation. Minimize mineral soil exposure by patchHard: Act At scarifying to establish seedlings. Elevated microsites generally preferred planting

spots. Mounding may be beneficial on finer-textured 09a. SSL 3-5; mediumseverity burn will generally be beneficial in improving soil temperature. High-severity burn required to control vegetation. 09a has higher risk of compaction andwindthrow.

Sx Pl is limited by shade intolerance and saturated soils. Sxw and Bl may be damaged[Ble Pl] by frost. Plant sites promptly with large, sturdy stock. Assess/control competingHard: Act At vegetation. Minimize mineral soil exposure by patch scarifying (10a) or mounding

(10b) to establish seedlings. Elevated microsites preferred planting spots (drainage,warmer soils, less frost). Consider cluster planting (see page 7•15) and reducedstocking. Sites often have higher risk of compaction and windthrow (finer textures,high water tables) and surface erosion (fluvial sites). SSL 4-5 (2-3 on 10a).

Pl Sb Sxw These sites are very marginal for timber production and should not be logged.High risk of frost damage on Sxw. Choose elevated microsites for planting.


e Moose browse on Bl should be expected throughout the SBSmc2.f Slashburning severity levels (SSL) are described in Section 7.2.6, page 7•27.

SBSmc2

7 • 73

7.3 Forest Health15

Tables 7.4 - 7.9 are provided to guide the user in anticipating andrecognizing pests that occur in the most prominent biogeoclimatic zonesof the PRFR. The tables do not show every pest that occurs in thesezones, but highlight those that are widespread or can cause seriousdamage to the host. Users should consider these tables as guides forensuring that future pest problems are considered at an early stage ofthe prescriptive process.

Hazard and risk

Hazard is defined as the state in which the host is susceptible. Risk is afunction of hazard and the presence of a pest. Pest hazard and risk canchange over the life of the host.

Some tree species are susceptible to certain pests during only a specificpart of their life cycle. When this hazard is high, a “window” exists forthe pest to take advantage of this opportunity. A high risk requires asusceptible host (i.e., high hazard), a vigorous pest, and the properconditions for a successful attack.

An example of this is mountain pine beetle and lodgepole pine. Duringthe early life of the pine, the hazard of attack is very low because thebeetle does not favour small-diameter trees. However, once the tree isover 80 years old it is usually of sufficient girth that the hazard to itbecomes high. The “window” is now present. The risk of attack isdetermined by the hazard and the proximity of the nearestbeetle-attacked stand. If that attack is 200 km away, the risk is fairlylow. If the nearest attack is 2 km away, the risk becomes high.

Using the tables

Only four biogeoclimatic zones are illustrated in the tables. There are tworeasons for this. The first is that the recorded history of pests in the PRFRis poor and we do not have information for the remaining zones. The otherreason is that, due to the widespread nature of some of these pests, usersshould be alert for them at all times when working in these zones.Segregation into ecological subzones or variants could lead to a falsesense of security when, in reality, it is a lack of data (rather than a lackof pests) that can lead to incorrect assumptions about pest distribution.Only the zones in which the host is a major species component are listed.

The tables are divided into four categories of host damage:

• Young stand mortality occurs between the regeneration stageand free growing.16

15 Contributed by Stefan Zeglen, Forest Pathologist, and Tim Ebata, ForestEntomologist, Prince Rupert Forest Region.

16 Further details on acceptability of host species in young stands are located in “FreeGrowing Standards for Northern B.C.” (Appendix I, Silviculture Manual Insert A,PRFR).

Silviculture

7• 74

• Growth reduction affects trees that are free growing and in astate of rapid incremental growth (to about culmination age).Pests listed here impede tree vigour and, in many cases, causemortality before rotation age.

• Mature stand mortality afflicts trees that are of sufficientsize and maturity to attract and harbour pests that acceleratesenescence and usually cause mortality (e.g., bark beetles, decayfungi).

• Loss of form occurs at any stage in tree development and is astem deformity that reduces wood quality (e.g., forks, crooks)and may indirectly cause mortality (e.g., cankers).

Pest species listed under damage categories are noted in two type faces.Bold type indicates pests that present a high risk and are a widespreadproblem in the zone. Species indicated in plain type face present a lowerrisk of attack or are limited to specific locations in the zone.

These tables provide specific information on most of the pest problemslikely to be encountered in the PRFR and should assist in thepreparation of PHSPs. For more information, consult Pre-HarvestSilvicultural Guidelines for Northern B.C. (Appendix I, SilvicultureManual Insert I, PRFR), or your local Forest Health specialist.

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7 • 75

TABLE 7.4. Major pests of spruce (Sitka, Engelmann, white, andhybrids) in four biogeoclimatic zones of the PRFR

Young stand Mature standZone mortality Growth reduction mortality Loss of form

CWH Voles,a Porcupine, Spruce bark beetle Spruce leaderFrost Tomentosus root Porcupine, weevil,d

disease, Windthrowc FrostAnnosus root disease,Decayb

ESSF Voles, Tomentosus root Spruce bark beetle, Ungulates,Frost disease, Windthrowc Frost

Spruce broom rust,Decay b

ICH Voles, Tomentosus root Spruce bark beetle, Spruce leaderRhizina root disease, Windthrowc weevil,d

disease, Spruce broom rust, FrostBlack army Decayb

cutworm,Frost

SBS Voles, Tomentosus root Spruce bark beetle, Ungulates,Rhizina root disease, Windthrowc Frostdisease, Spruce broom rust,Black army Decayb

cutworm,Frost

a Bold type indicates a high risk of attack by the pest without proper precautions or apest that has widespread presence in the zone. Normal type indicates lower risk ofattack by the pest, or occurrence only in specific locations within the zone.

b Commonly red ring rot (Phellinus pini), red belt fungus (Fomitopsis pinicola), orSchweinitzii butt rot (Phaeolus schweinitzii).

c If root system is exposed (i.e., root ball), check for signs of Tomentosus or other rootdisease. If stem is snapped low on the bole, check for signs of internal decays.

d Hazard rating zones based on degree-day accumulation are available from forestdistrict offices.

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TABLE 7.5. Major pests of lodgepole pine in four biogeoclimatic zones ofthe PRFR


CWH Volesa Tomentosus root Porcupine,disease, Mountain pine beetleDecay,b

Porcupine

ESSF Comandra Tomentosus root Mountain pine Atropellisblister rust, disease, beetle,c canker,Voles, Pl dwarf mistletoe, Porcupine StalactiformWestern gall rust, Decay,b blister rustHares Porcupine,

Squirrel

ICH Voles, Tomentosus root Mountain pine AtropellisComandra blister disease, beetle,c canker,rust, Pl dwarf mistletoe, Porcupine StalactiformRhizina root Decayb, blister rustdisease, PorcupineBlack armycutworm,Warren’s rootcollar weevil

SBS Comandra Tomentosus root Mountain pine Atropellisblister rust, disease, beetle,c canker,Voles, Pl dwarf mistletoe, Porcupine StalactiformWestern gall rust, Decay,b blister rust,Rhizina root Porcupine, Pl terminaldisease, Squirrel weevilBlack armycutworm,Warren’s rootcollar weevil,Hares


b Commonly red ring rot (Phellinus pini) or red belt fungus (Fomitopsis pinicola).c Hazard rating zones are available from forest district offices.

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TABLE 7.6. Major pests of amabilis fir and subalpine fir in four biogeoclimatic zones of the PRFR


CWH Volesa Tomentosus root Decayb Ungulatesdisease,Annosus rootdisease,Fir broom rust,Blackheadedbudworm

ESSF Voles Tomentosus root Balsam bark beetle, Ungulatesdisease, Decayb

Fir broom rust

ICH Rhizina root Tomentosus root Balsam bark beetle, Ungulatesdisease, disease, Decayb

Black army Fir broom rust,cutworm, WesternVoles blackheaded

budworm,Two-year-cyclebudworm

SBS Voles, Tomentosus root Balsam bark beetle, UngulatesRhizina root disease, Decayb

disease, Fir broom rust,Black army Two-year-cyclecutworm budworm,

Westernblackheadedbudworm

a Bold type indicates a high risk of attack by the pest without proper precautions or apest that has widespread presence in the zone. Normal type indicates lower risk ofattack by the pest, or occurrence only in specific locations within the zone

b Commonly Indian paint fungus (Echinodontium tinctorium) or red belt fungus(Fomitopsis pinicola).

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TABLE 7.7. Major pests of western hemlock in two biogeoclimatic zones of the PRFR


CWH Voles,a Hw dwarf Porcupine Ungulates,Frost mistletoe, Hemlock fluting,

Annosus root Frostdisease,Porcupine,Decay,b

Westernblackheadedbudworm

ICH Rhizina root Hw dwarf Porcupine Ungulates,disease, mistletoe, FrostVoles, Annosus rootFrost disease,

Tomentosus rootdisease,Decayb

a Bold type indicates a high risk of attack by the pest without proper precautions or a pest thathas widespread presence in the zone. Normal type indicates lower risk of attack by the pest, oroccurrence only in specific locations within the zone.

b Commonly Indian paint fungus (Echinodontium tinctorium), red belt fungus (Fomitopsispinicola), red ring rot (Phellinus pini), Schweinitzii butt rot (Phaeolus schweinitzii), quinineconk (Fomitopsis officinalis). or artist’s conk (Ganoderma applanatum).

TABLE 7.8. Major pests of western redcedar and yellow-cedar in twobiogeoclimatic zones of the PRFR


CWH Voles,a Phellinus root Yellow-cedar decline,d Ungulates,Deer, disease,b Decayc FrostFrost Annosus root

disease

ICH Rhizina root Phellinus root Decayc Ungulates,disease, diseaseb FrostVoles,Deer,Frost

a See footnote “a” in Table 7.7 above. b Phellinus weirii (cedar strain).c Mainly on Cw, and commonly redcedar pocket rot (Poria rivulosa), Indian paint fungus

(Echinodontium tinctorium), red belt fungus (Fomitopsis pinicola), or red ring rot (Phellinuspini).

d Causal agent uncertain.

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7 • 79

TABLE 7.9. Major pests of trembling aspen and black cottonwood in three biogeoclimatic zones of the PRFR

Young stand Mature standZone mortality Growth reduction mortality Loss of Form

CWH Shepherd’s crook Cankers,ab Decay,c

disease, Forest tent Poplar and willowVoles caterpillar borer

ICH Cankersb Decayc

SBS Cankersb Decayc


b Commonly Cytospora canker (Valsa sordida), sooty bark canker (Encoelia pruinosa),Hypoxylon canker (Hypoxylon mammatum), or Ceratocystis spp.

c Commonly aspen trunk rot (Phellinus tremulae), oyster mushroom (Pleurotusostreatus), artist’s conk (Ganoderma applanatum), or Pholiota spp.

7.4 Grass and Legume Seeding17

Seeding is a prescriptive practice involving many decisions about theneed to seed, species selection, rate of seeding, and method of application.Prescriptions should be made on a site-by-site basis, considering specificsite characteristics and the goals or objectives of seeding.

There are numerous research and operational seeding programs thathave provided useful information for developing prescriptions. Reports onspecific projects are available, as are commonly used handbooks on grassand legume seeding for specific uses, including Carr (1980), AlbertaAgriculture (1981), Chatwin et al. (1991), and Tingle (1992).

Many resource people are available for providing advice and referrals,including Range, Forest Sciences, Silviculture, Engineering, andProtection personnel with the Ministry of Forests; DistrictAgriculturalists and specialists with the Ministry of Agriculture,Fisheries and Food; and Agriculture Canada researchers in Kamloops,B.C. and Beaverlodge, Alta. Additional information is available from seedcompanies.

17 Contributed by Bob Drinkwater, Regional Range Agrologist, Prince RupertForest Region.

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7• 80

7.4.1 Developing a seeding prescription

The following seven steps should be taken when developing a seedingprescription:

1. Identify situations where seeding can be done and will havebeneficial effects. Forested sites are disturbed by activities such asharvesting, road construction, slashburning, and land clearing, and byevents such as wildfire, disease, or insect attack. Seeding can minimizeerosion and weed infestation, enhance the nutrient supply on a sitethrough nitrogen additions, and improve soil structure following suchdisturbances. Seeding can also be effective for vegetation management byreducing undesirable vegetation such as fireweed and thimbleberry,while improving forage production. As well, seeding can have significantbenefits when a suitable seedbed is created following a disturbance.

2. Set goals and objectives for the seeding project. Where possible,goals should be measurable.

3. Determine the appropriate seed mix. Commercial seed is availablefor numerous plant species. The species selected and ratios chosendepend on site conditions such as soil characteristics, climate and speciescompatibility, persistence of species, availability, and cost. Table 7.10provides several suggested seed mixes for different uses and siteconditions in the PRFR, and Table 7.11 outlines the attributes andtolerances of recommended grass and legume species. Generally, seedshould be applied in mixtures of two to five species in various ratios.More than five species in a mix suggests that the prescription is notspecific enough.

Commercially available species are usually available in numerousvarieties. Varieties will have the general attributes of the species, alongwith specific characteristics such as winter hardiness, yield, height, andthe absence of toxins. Specific varieties should be used if thesecharacteristics are important to attaining goals.

4. Determine the rate of seeding. The rate of seed unit is given innumber of seeds per unit area (e.g., seeds/m2), or weight of seeds per area(e.g., kg/ha). Seeding rate will depend on the goals and the cost of theseeding project. Seeding rates are adjusted as results from research andoperational trials become available. Seeding for silviculture purposes isusually prescribed at rates of 10 - 20 kg/ha. Seeding for erosion control isusually prescribed at 15 - 30 kg/ha for dry seeding and 50 - 80 kg/ha forhydroseeding. Interim forage seeding on cutblocks should be done atlower rates, usually 4 - 6 kg/ha. Seeding for forage production on morepermanent pastures is usually prescribed at rates of 6 - 18 kg/ha.Seeding for fire rehabilitation can range upwards from 4 kg/ha.

5. Determine application method. The method used to spread the seedon the disturbed ground will depend on the site conditions, the purpose ofthe seeding, and the time and money available to do the seeding. There are

Silviculture

7 • 81

several methods for applying seed, including hand scattering, manualcyclone seeders, cyclone seeders attached to helicopters or sitepreparation equipment, air-blown seeders, and hydro-seeders.

6. Determine timing of seeding. Sites should be seeded promptly afterdisturbance. The longer the delay, the greater the potential for soilerosion, site degradation, cementing of soils, and growth of undesirablevegetation including noxious weeds. It is important to consider thespecific soil moisture and temperature requirements for germination ofthe species included in the seed mix. Young germinants are susceptible todrought, frost, or excessive moisture or ponding. Timing of seedingshould allow for germination and adequate growth before adverseconditions set in.

7. Evaluate seeding projects. Past experience should he used toformulate future prescriptions. Successes and failures must be measuredand documented. Several methods are used to evaluate seedingeffectiveness, including the simple keeping of photographic records. Toevaluate operational seeding, two methods are suggested: that outlinedin B.C. Ministry of Environment and Ministry of Forests (1990), and thatoutlined in Northern Interior Vegetation Management Association (1990)(referred to as the NIVMA method). Assessment of Rhizobium infectionin legumes should follow B.C. Ministry of Forests (1991).

Silviculture

7• 82

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Silviculture

7 • 83

TABLE 7.11. Attributes and tolerances of recommended grass andlegume species for use in seed mixes in the PRFR

Species Attributes Rooting profile Moisture/climate factors

Legumes

Alfalfa - Medium-lived - Deep, 3-9 m - SBS/ICHMedicago perennial - Taproot - Wide range of conditionssativa - Up to 1 m tall - Creeping variety - Drought tolerant

- Persists 4-10 yr also available - Intolerant of extended flooding- N-fixer - Some varieties very winter hardy

Alsike clover - Short-lived perennial - Deep, into subsoil - All zonesTrifolium - Persists 4-5 yr - Many-branched - Wide range of conditionshybridum - Spreads by seed and root - Tolerant of moist areas

root fragments - Tolerant of cold and frost heaving- N-fixer - Intolerant of drought, high

temperature, and shade

Birds-foot - Long-lived perennial - Deep - CWH/ICH/SBStrefoil - Persists 10+ yr? - Strong taproot, - Unsuitable for dry sitesLotus - Spreads by seed and with many side - Withstands floodingcorniculatus root fragments branches

Red clover - Short-lived perennial - Shallow - All zonesTrifolium - Persists 2-3 yr - Weak taproot with - Wide range of conditionspratense - Spreads by seed many fibrous, side - Tolerant of cold and frost heaving

branches

Sweet-clover - Biennial - Deep - Poor establishment in PRFRMelilotus - 1-2 m tall - Very strong taproot - Intolerant of cold, wet, andalba, M. - Abundant first few floodingofficinalis years

- Spreads by seed- N-fixer

White clover - Long-lived perennial - Shallow, 1 m - All zones, ESSF variableTrifolium - Persists for several - Taproot - Low drought tolerancerepens years - Stolons root at - Requires constant moisture

- Animal-dispersed nodes supplyseed; stoloniferous - Intolerant of prolonged flooding

Grasses

Italian rye - Short-lived annual - Very shallow, 5 cm - CWH/ICH/SBSgrass (biennial) - Dense fibrous mass - Survives short periods of floodingLolium - Rare after 1 year of roots - Intolerant of droughtmultiflorum - Limited seeding

Creeping red - Long-lived perennial - Shallow - All zonesfescue - Persists - Dense fibrous - Tolerates high rainfall, springFestuca rubra - Spreads by seed and roots, strong sod- flooding, and shadessp. rubra rhizomes former - Withstands some drought

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7• 84

Soil factors Other considerations and special uses

- Well-drained soils, high lime - Very competitivecontent - Good N-fixer, enhances degraded sites

- Some alkalinity/salinity - - Can compete with tree seedlings- Sensitive to acid - Growth is limited at low pH

- Suited to acidic, organic soils - Quick and easy to establish- Heavy, moist alkaline soils - Good nurse crop for accompanying species- Waterlogged soils - Good N-fixer, improves soil

- Waterlogged soils - More consistent to establish compared with- Acid soils, low fertility white clover

- Acid soils - Sometimes an alternative for alsike clover,but doesn’t do as well in poorly drainedareas

- Fertile, well-drained, clayey to - Breaks up subsurface compactionclay-loamy soils - Height can cause problems for tree

- Sensitive to acid soils seedlings for 3-4 years- Intolerant of waterlogged

soils, poor drainage

- Slightly acidic soils - Slow to establish, but persists (not as- Low tolerance for saline or consistent as alsike or trefoil)

alkaline soils - Mat-forming, very effective in preventing- Poor response on waterlogged soil erosion and for soil enhancement

soils

- Wide range of soil types - Establishes very quickly- Heavy clay, poorly drained - Good for minimizing soil erosion and weed

soils infestation- Medium to high soil fertility - Nurse crop for slower-establishing species

- Clayey, loamy and sandy soils - Prefers well-disturbed seedbed- Very tolerant of acidity, low - Good for erosion control, broadcast burns

fertility, salinity, and - Specify turf type for silvicultural seedingwaterlogged soils - Grows in areas too dry for timothy

Silviculture

7 • 85

TABLE 7.11 (Continued)

Species Attributes Rooting profile Moisture/climate factors

Chewings - Long-lived perennial - Shallow - ICH/SBS/probably CWHfescue - Forms dense stands - Dense fibrous roots - Tolerant of some shading andFestuca rubra - Spreads vegetatively droughtvar. comm. and by seeds

Fall rye - Short-lived annual -- - ICH/possibly all zonesSecale spp. - Persists 1-2 yr

- Spreads by seed

Kentucky - Long-lived perennial - Shallow, 5 cm - All zonesbluegrass - Spreads by seeds and - Roots extensively - Best in cool, humid climatesPoa pratensis rhizomes branched, forming - Tolerant of severe drought

a very dense sod - Slightly shade tolerant

Orchardgrass - Long-lived perennial - Deep - All zonesDactylis - Bunchgrass - Dense, fibrous root - Relatively drought tolerantglomerata - Spreads by seed and system - Most shade tolerant of the grasses

tillering

Perennial - Short-lived perennial - Shallow - CWH/ICH/SBSryegrass - 1-2 yr - Fibrous root - Survives short periods of floodingLolium system - Intolerant of droughtperenne

Redtop - Long-lived perennial - Shallow - All zonesAgrostis alba - Sod-grass - Extensively

- Spreads by seed and branched rootsrhizomes

Reed - Long-lived perennial - Deep - Ponds and bogs in all zonescanarygrass - Sod-grass - Grows in clumps - Thrives under flooded conditionsPhalaris - Spreads by rhizomes with rhizomes that or in areas with heavy rainfallarundinacea and seed form dense sods - Somewhat drought tolerant

Smooth - Long-lived perennial - Deep - SBS/probably ICHbrome - Sod-grass - Rhizomatous - Tolerates some flooding in springBromus - Spreads aggressivelyinermis by rhizomes

Tall fescue - Long-lived - Deep - SBS/ICH/probably all zonesFestuca - Bunchgrass - Roots can break up - Wide range of conditions, bestarundinacea - Spreads by seed and compacted soil at under cool conditions

underground stems lower depths - Good drought tolerance

Timothy - Perennial - Shallow, but can - SBS/ICH/probably all zonesPhleum - Spreads by new reach depths of - Cool moist areaspratense shoots from the base 1 m - Withstands some spring flooding

of older culms; - Fibrous roots - Low drought toleranceprolific seed- - Winter hardyproducer

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7• 86

Soil factors Other considerations and special uses

- Clayey, loamy, and sandy soils - Suppresses unwanted vegetation such as- Very tolerant of acidity, low fireweed and thimbleberry

fertility, salinity, and - Successfully seeded on broadcast burnswaterlogged soils

- Relatively tolerant of low - Good nurse cropacidity, low fertility, high clay or - Establishes quickly, good for erosion sand content, or poor drainage control, weed control, and aesthetic

purposes

- Well-drained, highly productive - Slow establishment, but very aggressivelimestone-derived soils - Palatable

- Slightly acid tolerant

- Requires good drainage - Very high yields of quality forage- Tolerant of moderate salinity and - Quick regrowth following grazing

acidity - Use winter-hardy varieties in windblown areas

- Medium to high fertility - A nurse crop assisting longer-lived species- Wide range of soils, including to establish

those with high clay content, and - Quick to establish for erosion and weedpoor drainage control

- Tolerates high acidity, clay soils, - Very aggressive low fertility, and poor drainage - Low palatability

- Used in coastal areas for erosion control

- Very tolerant of waterlogging - Requires a good seedbed- Withstands acidity, alkalinity - Slow to establish- Can be used on organic soils - Expensive and in short supply

- Wide range of soils - Slow to establish, but very persistent- Prefers good drainage - Good forage species- Tolerates alkalinity, salinity,

and acidity

- Wide range of soil conditions - Slow to establish- Tolerates poor drainage, - Good soil improver

alkalinity, acidity, and salinity

- Very tolerant of acidity - Good for seeding wet areas, between reed- Suited to peaty areas, and canarygrass and orchardgrass

waterlogged soils - Good forage species- Thrives on clayey, silty, and

sandy soils

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7 • 87

Silviculture

7• 88

8 LITERATURE CITEDAgriculture Canada Expert Committee on Soil Survey. 1987. The

Canadian system of soil classification. 2nd ed. Agric. Can. Publ.1646.

Alberta Agriculture. 1981. Alberta forage manual. Agdex 120/20-4.Edmonton, Alta.

Banner, A., R.N. Green, A. Inselberg, K. Klinka, D.S. McLennan, D.V.Meidinger, F.C. Nuszdorfer, and J. Pojar. 1990. Site classificationfor coastal British Columbia (pamphlet). B.C. Min. For., Victoria,B.C.

Banner, A., R.J. Hebda, E. T. Oswald, J. Pojar, and R. Trowbridge. 1988.Wetlands of Pacific Canada. In National Wetlands Working Group.Wetlands of Canada. Ottawa, Ont. Polyscience, pp. 306-346.

Banner, A., J. Pojar, and G.E. Rouse. 1983. Postglacial paleoecology andsuccessional relationships of a bog woodland near Prince Rupert,British Columbia. Can. J. For. Res. 13:938-947.

Banner, A., J. Pojar, and R. Trowbridge. 1986. Representative wetlandtypes of the northern part of the Pacific Oceanic Wetland Region.B.C. Min. For., Victoria, B.C. Res. Rep. 85008-PR.

B.C. Ministry of Environment and Ministry of Forests. 1990. Proceduresfor environmental monitoring in range and wildlife habitatmanagement. B.C. Min. Environ., Victoria, B.C.

B.C. Ministry of Forests. 1991. Field guide to nodulation and nitrogenfixation assessment. B.C. Min. For., Victoria, B.C. Land Manage.Handb. Field Guide Insert 4.

Braumandl, T. and M.P. Curran. 1992. A field guide for site identificationand interpretation in the Nelson Forest Region. B.C. Min. For.,Victoria, B.C. Land Manage. Handb. No. 20.

Campbell, R.W., N.K. Dawe, I. McTaggart-Cowan, J.M. Cooper, G.W.Kaiser, and M.C.E. McNall. 1990. The birds of British Columbia.Vol. 1. Royal B.C. Museum, Victoria, B.C.

Cart, W.W. 1980. Handbook for forest roadside surface erosion control inBritish Columbia. B.C. Min. For., Victoria, B.C. Land Manage.Rep. No. 4.

Chatwin, S.C., D.E. Howes, J.W. Schwab, and D.N. Swanston. 1991. Aguide for management of landslide-prone terrain in the PacificNorthwest. B.C. Min. For., Victoria, B.C. Land Manage. Handb.No. 18.

8 • 1

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Coates, D., S. Haeussler, and J. Bather. 1990. A guide to the response ofcommon plants in British Columbia to management treatments.B.C. Min. For. and For. Can., Victoria, B.C. FRDA Handb. No. 008.

Conard, S.G. 1984. Forest vegetation management in British Columbia:problem analysis. B.C. Min. For., Victoria, B.C. Res. Rep.RR84001-HQ.

Courtin, P.O., R.N. Green, and G. Shishkov. 1989. An ecological approachto organizing forests for woodlot management. B.C. Min. For.,Victoria, B.C. Land Manage. Rep. No. 58.

Demarchl, D.A., R.D. Marsh, A.P. Harcombe, and E.C. Lea. 1990. Theenvironment. In R.W. Campbell, P.M. Dawe, I. McTaggart-Cowan,J.M. Cooper, G.W. Kaiser, and M.C.E. McNall. The birds of BritishColumbia. Vol. 1. Royal B.C. Museum, Victoria, B.C.

Douglas, G.W., G.B. Straley, and D. Meidinger. 1989. The vascular plantsof British Columbia. Part 1. Gymnosperms and Dicotyledons(Aceraceae through Cucurbitaceae). B.C. Min. For., Victoria, B.C.Special Report Series 1.

______. 1990. The vascular plants of British Columbia. Part 2.Dicotyledons (Diapensiaceae through Portulaceae). B.C. Min. For.,Victoria, B.C. Special Report Series 2.

______. 1991. The vascular plants of British Columbia. Part 3.Dicotyledons (Primulaceae through Zygophyllaceae andPteridophytes. B.C. Min. For., Victoria, B.C. Special Report Series3.

______. 1993. The vascular plants of British Columbia. Part 4.Monocotyledons. B.C. Min. For., Victoria, B.C. Special ReportSeries 4. In press.

Green, R.N., P.O. Courtin, K. Klinka, R.J. Slaco, and C.A. Ray. 1984. Sitediagnosis, tree species selection and slash burning guidelines forthe Vancouver Forest Region. Abridged version. B.C. Min. For.,Vancouver, B.C. Land Manage. Handb. No. 8.

Green, R.N., R.L. Trowbridge, and K. Klinka. 1993. Towards a taxonomicclassification of humus forms. For. Sci. Monogr. 29.

Haeussler, S., D. Coates, and J. Mather. 1990. Autecology of commonplants in British Columbia. B.C. Min. For. and For. Can., Victoria,B.C. FRDA Rep. 158.

Hamilton, E. 1988. A system for the classification of seral ecosystemswithin the biogeoclimatic ecosystem classification. First approx.B.C. Min. For. Lands, Victoria, B.C. Res. Rep. RR87004-HQ.

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Holland, S.S. 1976. Landforms of British Columbia: a physiographicoutline. 2nd ed. B.C. Dep. Mines Mineral Resources, Victoria, B.C.Bull. No. 48.

Howes, D.E. and E. Kenk. 1988. Terrain classification system for BritishColumbia. Revised ed. B.C. Min. Environ. and Min. Crown Lands,Victoria, B.C. Min. Environ. Manual 10.

Hunter, M.L. Jr. 1990. Wildlife, forests, and forestry: principles ofmanaging forests for biological diversity. Prentice Hall, Inc.,Englewood Cliffs, N.J.

Ireland, R.R., G.R. Brassard, W.B. Schofield, and D.H. Vitt. 1987.Checklist of the mosses of Canada II. Lindbergia 13:1-62.

Kayahara, G.J., G.G. Wang, and K. Klinka. 1993. Site index ofEnglemann spruce and subalpine fir, and its relationship tomeasures of ecological site quality in the ESSF zone of BritishColumbia. 1992/1993 Progress Rep., Univ. B.C. For. Sciences Dep.,Vancouver, B.C.

Klinka, K., R.E. Carter, G.F. Weetman, and M. Jull. 1992. Silviculturalanalysis of the subalpine mountain hemlock forest. B.C. Min. For.,Burnaby, B.C. Contract rep.

Klinka, K. and M.C. Feller. 1984. Principles used in selecting tree speciesfor regeneration of forest sites in southwestern British Columbia.For. Chron. 60(2):77-85.

Klinka, K., M.C. Feller, R.I. Green, D.V. Meidinger, J. Pojar, and J.Worrall. 1990. Ecological principles: applications. Chapter 6. InD.P. Lavender, R. Parish, C.M. Johnson, G. Montgomery, A. Vyse,R.A. Willis, and D. Winston. Regenerating British Columbia’sforests. For. Can. and B.C. Min. For., Univ. B.C. Press, Vancouver,B.C.

Klinka, K., V.J. Krajina, A. Ceska, and A.M. Scagel. 1989. Indicatorplants of coastal British Columbia. B.C. Min. For. and For. Can.FRDA. Univ. B.C. Press, Vancouver, B.C.

Krajina, V.J. 1969. Ecology of forest trees in British Columbia. Ecol. W.N. Am. 2(1):1-146.

Krajina, V.J., K. Klinka, and J. Worrall. 1982. Ecological characteristicsof trees and shrubs of British Columbia. Univ. B.C., Vancouver,B.C.

Lavender, D.P., R. Parish, C.M. Johnson, G. Montgomery, A. Vyse, R.A.Willis, and D. Winston. 1990. Regenerating British Columbia’sforests. For. Can. and B.C. Min. For., Univ. B.C. Press, Vancouver,B.C.

Lloyd, D., K. Angove, G. Hope, and C. Thompson. 1990. A guide to siteidentification and interpretation for the Kamloops Forest Region.B.C. Min. For., Victoria, B.C. Land Manage. Handb. No. 23.

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8 • 3

Luttmerding, H.A., D.A. Demarchi, E.C. Lea, D.V. Meidinger, and T. Vold.1990. Describing ecosystems in the field. 2nd ed. B.C. Min.Environ. and Min. For., Victoria, B.C. Min. Environ. Manual 11.

MacKinnon, A., C. DeLong, and D. Meidinger. 1990. A field guide foridentification and interpretation of ecosystems of the Northwestportion of the Prince George Forest Region. B.C. Min. For.,Victoria, B.C. Land Manage. Handb. No. 21.

MacKinnon, A., D. Meidinger, and K. Klinka. 1992. Use of thebiogeoclimatic ecosystem classification system in British Columbia.For. Chron. 68(1):100-120.

MacKinnon, A., J. Pojar, and R. Coupé (editors). 1992. Plants of northernBritish Columbia. B.C. Min. For. and For. Can. FRDA. Lone PinePubl., Edmonton, Alta.

McLennan, D.S. 1989. Summary of site index statistics for lodgepole pineand interior spruce in ecosystems of the Sub-Boreal Spruce andSub-Boreal Pine – Spruce biogeoclimatic zones. B.C. Min. For.,Victoria, B.C. Contract rep.

Marsh, R.D. 1988. Macroclimatic regions of British Columbia. In Land/wildlife integration workshop No. 3, Mont Ste. Marie, Que., Sept.16-19, 1985.

Meidinger, D. 1988. Recommended vernacular names for common plantsof British Columbia. B.C. Min. For. Lands, Victoria, B.C. Res. Rep.RR88002-HQ.

Meidinger, D. and J. Pojar (compilers and editors). 1991. Ecosystems ofBritish Columbia. B.C. Min. For., Victoria, B.C. Special ReportSeries 6.

Mitchell, W.R., R.N. Green, G.D. Hope, and K. Klinka. 1989. Methods forbiogeoclimatic ecosystem mapping. B.C. Min. For., Victoria, B.C.Res. Rep. RR89002-KL.

Newton, M. and P.G. Comeau. 1990. Control of competing vegetation.Chapter 19. In D.P. Lavender, R. Parish, C.M. Johnson, G.Montgomery, A. Vyse, R.A. Willis, and D. Winston. RegeneratingBritish Columbia’s forests. For. Can. and B.C. Min. For., Univ.B.C. Press, Vancouver, B.C.

Noble, W.J., T. Ahti, G.F. Otto, and I.M. Brodo. 1987. A second checklistand bibliography of the lichens and allied fungi of BritishColumbia. Syllogeus 61, National Museums of Canada, Ottawa,Ont.

Northern Interior Vegetation Management Association. 1990. A unifiedsystem of silvicultural monitoring. Prince George, B.C.

Pojar, J., K. Klinka, and D.V. Meidinger. 1987. Biogeoclimatic ecosystemclassification in British Columbia. For. Ecol. Manage. 22:119-154.

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8• 4

Pojar, J., F.C. Nuszdorfer, D. Demarchi, M. Fenger, and B. Fuhr. 1988.Biogeoclimatic and ecoregion units of the Prince Rupert ForestRegion. Two 1:500 000 map sheets. B.C. Min. For. Lands, Victoria,B.C.

Radcliffe, G., G. Porter, B. Bancroft, and C. Cadrin. 1993. Biodiversity ofthe Prince Rupert Forest Region. B.C. Min. For., Victoria, B.C.Land Manage. Rep. No. 82. In press.

Roberts, A. 1984. Guide to wetland ecosystems of the Sub-Boreal Spruce“a” subzone, Cariboo Forest Region, British Columbia. B.C. Min.For., Williams Lake, B.C. Unpubl. rep.

Silviculture Interpretations Working Group. 1993. Correlated guidelinesfor tree species selection (1st approx.) and stocking standards (2ndapprox.) for the ecosystems of British Columbia. B.C. Min. For.and For. Can., Victoria, B.C.

Stathers, R.J., R. Trowbridge, D.L. Spittlehouse, A. Macadam, and J.P.Kimmins. 1990. Ecological principles: basic concepts. Chapter 5. InD.P. Lavender, R. Parish, C.M. Johnson, G. Montgomery, A. Vyse,R.A. Willis, and D. Winston. Regenerating British Columbia’sforests. For. Can. and B.C. Min. For., Univ. B.C. Press, Vancouver,B.C.

Steen, O.A. and R.L. Roberts. 1988. Guide to wetland ecosystems of thevery dry montane Interior Douglas-fir subzone, eastern FraserPlateau variant (IDFb1) in the Cariboo Forest Region. B.C. Min.For. Lands, Victoria, B.C. Land Manage. Rep. No. 55.

Steventon, J.D. [1993]. Biodiversity and forest management in the PrinceRupert Forest Region. B.C. Min. For., Victoria, B.C. Land Manage.Rep. (in prep.).

Stickney, P.F. 1986. First decade plant succession following theSundance forest fire, northern Idaho. U.S. Dep. Agric. For. Serv.,Intermountain Res. Sta., Ogden, Utah. Gen. Tech. Rep. INT-197.

Stotler, R. and B. Crandall-Stotler. 1977. A checklist of the liverwortsand hornworts of North America. The Bryologist 80:405-428.

Thomson, S., J. Pojar, and A. Banner. [1993]. Initial succession followingwildfire in the Sub-Boreal Spruce zone, north central BritishColumbia: the first ten years. B.C. Min. For., Victoria, B.C. (inprep.).

Thrower, J. and A.F. Nussbaum. 1991. Site index curves and tables forBritish Columbia: coastal species. B.C. Min. For., Victoria, B.C.Land Manage. Handb. Field Guide Insert 3.

Thrower, J., A.F. Nussbaum, and C.M. Di Lucci. 1991. Site index curvesand tables for British Columbia: interior species. B.C. Min. For.,Victoria, B.C. Land Manage. Handb. Field Guide Insert 6.

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8 • 5

Tingle, J.N. (editor). 1992. B.C. forage. Reference binder. B.C. Min.Agric., Fisheries and Food, and B.C. Forage Council. Victoria, B.C.

Trowbridge, R., S. Schmidt, and L. Bedford. 1989. Slashburning severityguidelines for the Moist Cold Sub-Boreal Spruce subzone (SBSmc)in the Prince Rupert Forest Region. 1st approx. B.C. Min. For.,Victoria, B.C. Insert for the Sub-Boreal Spruce Zone Field Guide.Land Manage. Handb. No. 10.

Wang, Q., G. Wang, D. Coates, and K. Klinka. [1992]. Use of site factorsin the prediction of lodgepole pine and hybrid white spruce siteindex in the SBS zone of the Prince Rupert Forest Region. B.C.Min. For., Victoria, B.C. Res. Note (in prep.).

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8• 6

Wood horsetailEquisetum sylvaticum

Swamp horsetailEquisetum fluviatile

Common horsetailEquisetum arvense

A • 1

Appendices

Appendices

A• 2

APPENDIX 1. Ecosystem classification,interpretive, and plant guide references relevant to the PRFR

1 Ecosystem Classification References

Banner, A. 1983. Classification and successional relationships of somebog and forest ecosystems near Prince Rupert, British Columbia.M.Sc. thesis. Univ. B.C., Vancouver, B.C.

__________. 1985. Ecosystem classification and mapping in the CoastalWestern Hemlock Zone, Mid-Coast Drier Transitional Subzone(CWHh), Kimsquit River Valley, British Columbia. B.C. Min. For.,Res. Section., Smithers, B.C. Unpubl. rep.

Banner, A., R.N. Green, A. Inselberg, K. Klinka, D.S. McLennan, D.V.Meidinger, F.C. Nuszdorfer, and J. Pojar. 1990. Site classificationfor coastal British Columbia. B.C. Min. For., Victoria, B.C.

Banner, A., R.J. Hebda, E.T. Oswald, J. Pojar, and R. Trowbridge. 1988.Wetlands of Pacific Canada. In National Wetlands Working Group.Wetlands of Canada, Ottawa, Ont. Polyscience, pp. 306-346.

Banner, A. and J. Pojar. 1987. Ecosystem classification of the CoastalWestern Hemlock Zone, Hypermaritime Subzone (CWHhm) withinthe Mid Coast, North Coast, and Queen Charlotte Islands TimberSupply Areas. B.C. Min. For. Lands, Res. Section, Smithers, B.C.Unpubl. rep.

Banner, A., J. Pojar, J.W. Schwab, and R. Trowbridge. 1989. Vegetationand soils of the Queen Charlotte Islands: recent impacts ofdevelopment. In G.G.E. Scudder and N. Gessler (editors). Theouter shores. Based on the proceedings of the Queen CharlotteIslands first international scientific symposium, Univ. B.C., Aug.1984. Queen Charlotte Islands Museum Press, Skidegate, B.C., pp.261-279.

Banner, A., J. Pojar, and R. Trowbridge. 1983. Ecosystem classification ofthe Coastal Western Hemlock Zone, Queen Charlotte IslandsSubzone (CWHg), British Columbia. B.C. Min. For., Res. Section,Smithers, B.C. Unpubl. rep.

__________. 1986. Representative wetland types of the northern part ofthe Pacific Oceanic Wetland Region. B.C. Min. For., Victoria, B.C.Res. Rep. 85008-PR.

Other References

A • 3

Banner, A., J. Pojar, R. Trowbridge, and A. Hamilton. 1985. Grizzly bearhabitat in the Kimsquit River valley, coastal British Columbia:classification, description, and mapping. In G. P. Contreras andK.E. Evans (compilers). Proc. Grizzly Bear Habitat Symp.,Missoula, Mont., April 30 - May 2, 1985. U.S. Dep. Agric. For.Serv., Intermountain For. Range Exp. Sta., Ogden, Utah. Gen.Tech. Rep. INT-207, pp. 36-49.

Cichowski, D.B. and A. Banner. 1993. Management strategy and optionsfor the Tweedsmuir-Entiako caribou winter range. B.C. Min. For.,Victoria, B.C. Land Manage. Rep. No. 83. In press.

Clement, C.J.E. 1988. Biogeoclimatic units and ecosystem associations ofTree Farm License 41 - South Half. Shearwater EcologicalServices, Victoria, B.C. Unpubl. rep.

__________. 1990. Ecosystem units of the Khutzeymateen and Kateendrainages. B.C. Min. For., For. Sci. Section, Smithers, B.C. Draftrep.

Clement, C.J.E. and A. Banner. 1992. Ecosystem mapping of the DateCreek silvicultural systems research area, Prince Rupert ForestRegion. B.C. Min. For., For. Sci. Section, Smithers, B.C. Unpubl.rep.

Clement, C.J.E. and M. Fenger. 1981a. Forest zonation, vegetationlandscapes, and general terrain description for the Level MountainRange. 1:50 000 map. B.C. Min. Environ., Victoria, B.C.

__________. 1981b. Forest zonation, vegetation landscapes, and generalterrain description for the Horseranch Range. 1:50 000 map. B.C.Min. Environ., Victoria, B.C.

Delong, C., D. Tanner, and M. Jull. 1993. A field guide to siteidentification and interpretation for the southwestern portion ofthe Prince George Forest Region. B.C. Min. For., Victoria, B.C.Land Manage. Handb. No. 24.

Fenger, S.A. and R.C. Kowall. 1992. Biophysical soil landscape inventoryof the Stikine-Iskut area (mapsheets 104F, 104G, and parts of104B and 104H). B.C. Min. Environ., Lands, Parks, Victoria, B.C.

Fenger, M.A., T. Lea, B. Fuhr, and D. Demarchi. 1990. Wildlife habitatmap, Skeena North. Map at 1:500 000. B.C. Min. Environ.,Victoria, B.C.

Green, J.N., P.J. Courtin, and K. Klinka. [1993]. A field guide for siteidentification and interpretation in the Vancouver Forest Region.B.C. Min. For., Victoria, B.C. Land Manage. Rep. (in prep.).

Haeussler, S., J. Pojar, B.M. Geisler, D. Yule, and J.M. Annas. 1984. Aguide to the Coastal Western Hemlock Zone, Northern DrierMaritime Subzone (CWHf) in the Prince Rupert Forest Region.B.C. Min. For., Smithers, B.C. Land Manage. Rep. No. 21.

Other References

A• 4

___________. 1985. A guide to the interior Cedar – Hemlock Zone,Northwestern Transitional Subzone (ICHg), in the Prince RupertForest Region, British Columbia. B.C. Min. For., Victoria, B.C.Land Manage. Rep. No. 26.

Houseknecht, S., S. Haeussler, A. Kokoshke, J. Pojar, D. Holmes, B.M.Geisler, D. Yole, and C. Clement. 1987. A field guide foridentification and interpretation of the Interior Cedar – HemlockZone, northwestern transitional subzone (ICHg), in the PrinceRupert Forest Region. B.C. Min. For., Lands, Victoria, B.C. LandManage. Handb. No. 12.

Ketcheson, M. 1989. Atlin biophysical inventory: vegetation. B.C. Min.Environ., Smithers, B.C. Unpubl. rep.

Lewis, T., J. Pojar, D. Holmes, R. Trowbridge, and K.D. Coates. 1986. Afield guide for identification and interpretation of the Sub-BorealSpruce Zone in the Prince Rupert Forest Region. B.C. Min. For.,Victoria, B.C. Land Manage. Handb. No. 10.

Lewis, T., D. Yole, J. Pojar, D. Holmes, and A. Inselberg. 1989. A fieldguide for identification and interpretation of the EngelmannSpruce – Subalpine Fir Zone in the Prince Rupert Forest Region,British Columbia. B.C. Min. For., Victoria, B.C. Land Manage.Handb. No. 27.

Lindeburgh, S. and R. Trowbridge. 1985. Production of forestryinterpretive maps and management summaries from ecologicallybased polygons. Can. Soil Sci. Meetings, Banff, Alta. Aug. 26 - 29,1984. B.C. Min. For., Victoria, B.C. Res. Rep. RR85001-PR.

MacKenzie, W. and A. Banner. 1991. Ecosystems of the SmithersCommunity Forest. B.C., Min. For., For. Sci. Section, Smithers,B.C. Unpubl. rep.

MacKinnon, A., C. DeLong, and D. Meidinger. 1990. A field guide foridentification and interpretation of ecosystems of the northwestportion of the Prince George Forest Region. B.C. Min. For.,Victoria, B.C. Land Manage. Handb. No. 21.

McLennan, D.S. and A. Mamias. 1992. Ecosystem classification and siteindex-site unit correlations for the CWHvm biogeoclimatic subzonenear Prince Rupert, British Columbia. B.C. Min. For., For. Sci.Section, Smithers, B.C. Unpubl. contract rep.

Pojar, J. 1982. Boreal and subalpine grasslands. B.C. Min. For.,Smithers, B.C. Unpubl. man.

___________. 1985. Vegetation and ungulate habitat in the Gladys LakeEcological Reserve, northern British Columbia. B.C. Min. For.,Victoria, B.C.

Other References

A • 5

__________. 1991. Subalpine and alpine vegetation of the Gladys LakeEcological Reserve, northern British Columbia. Contr. NaturalScience, Royal B.C. Museum, Victoria, B.C. 12:1-28.

Pojar, J., F.C. Nuszdorfer, D. Demarchi, M. Fenger, and B. Fuhr. 1988.Biogeoclimatic and ecoregion units of the Prince Rupert ForestRegion. Two 1:500 000 map sheets. B.C. Min. For. Lands, Victoria,B.C.

Pojar, J., R. Trowbridge, and D. Coates. 1984. A guide to theclassification and interpretation of the Sub-Boreal Spruce Zone,Prince Rupert Forest Region, British Columbia. B.C. Min. For.,Victoria, B.C. Land Manage. Rep. No. 17.

Pojar, J., R. Trowbridge, and T. Lewis. 1983. Biogeoclimatic zones of theCassiar Timber Supply Area, northwestern British Columbia. B.C.Min. For., Res. Section, Smithers, B.C. Unpubl. rep.

Roberts, A. 1984. Guide to wetland ecosystems of the Sub-Boreal Spruce“a” subzone, Cariboo Forest Region, British Columbia. B.C. Min.For., Williams Lake, B.C. Unpubl. rep.

Simonar, K., C. Audet, W. Lambkin, M. Hochachka, and A. Banner. 1993.Classification of the Iskut-Stikine Variant of the Very Wet, Cold,Interior Cedar – Hemlock Subzone (ICHvc2) in the Prince RupertForest Region. B.C. Min. For., For. Sci. Section, Smithers, B.C.Unpubl. contract rep.

Standish, J.T., S. Haeussler, A. Kokoshke, J. Pojar, D. Holmes, B.M.Geisler, and D. Yole. 1987. A field guide for identification andinterpretation of the Coastal Western Hemlock Zone, NorthernDrier Maritime Subzone (CWHf), in the Prince Rupert ForestRegion. B.C. Min. For., Victoria, B.C. Land Manage. Handb. No.14.

Talisman Land Resource Consultants. 1984a. Biogeoclimatic mapping,Kitimat, T.F.L. #41, for Eurocan Pulp and Paper Co. Ltd. VolumeI: Report, Vancouver, B.C. Unpubl. rep.

__________. 1984b. Biogeoclimatic mapping, Kitimat, T.F.L. # 41, forEurocan Pulp and Paper Co. Ltd. Volume II: Data. Vancouver,B.C. Unpubl. rep.

Trowbridge, R., J. Pojar, and T. Lewis. 1983. Interim classification of theBoreal White and Black Spruce biogeoclimatic zone in the PrinceRupert Forest Region. B.C. Min. For., Res. Section, Smithers, B.C.Unpubl. rep.

Yole, D., J. Pojar, and B. Robinson. 1982. Ecosystem Classification of theCoastal Western Hemlock Zone within the Mid-Coast TimberSupply Area, Prince Rupert Forest Region, British Columbia. B.C.Min. For., Res. Section, Smithers, B.C. Unpubl. rep.

Other References

A• 6

2 Site and Silvicultural Interpretation Reports

B.C. Ministry of Forests. 1991a. Field guide to nodulation and nitrogenfixation assessment. B.C. Min. For, Victoria, B.C. Land Manage.Handb. Field Guide Insert 4.

__________. 1991b. Silvicultural systems: their role in British Columbia’sforest management. Victoria, B.C.

Camenzind, W.G. 1989. The review of silvicultural systems and theirapplicability to the Prince Rupert Forest Region, interior subzones.B.C. Min. For., Smithers, B.C. Contract rep.

Carr, W.W., W.R. Mitchell, and W.J. Watt. 1991. Basic soilinterpretations for forest development planning: surface soilerosion and soil compaction. B.C. Min. For., Victoria, B.C. LandManage. Rep. No. 63.

Chatwin, S.C., D.E. Howes, J.W. Schwab, and D.N. Swanston. 1991. Aguide for management of landslide-prone terrain in the PacificNorthwest. B.C. Min. For., Victoria, B.C. Land Manage. Handb.No. 18.

Coates, D. and S. Haeussler. 1987. A guide to the use of mechanical sitepreparation equipment in north central British Columbia. 2nd ed.B.C. Min. For., For. Can., and Northern Silv. Comm. FRDAHandb. No. 002.

Coates, D., S. Haeussler, and J. Mather. 1990. A guide to the response ofcommon plants in British Columbia to management treatments.B.C. Min. For. and For. Can., Victoria, B.C. FRDA Handb. No. 008.

Curran, M., B. Fraser, L. Bedford, M. Osberg, and B. Mitchell. 1990. Sitepreparation strategies to manage soil disturbance. Interior sites.B.C. Min. For., Victoria, B.C. Land Manage. Handb. Field GuideInsert 2.

Finck, K.E., P. Humphreys, and G.V. Hawkins. 1989. Field guide to pestsof managed forests in British Columbia. B.C. Min. For. and For.Can., Victoria, B.C. Joint Rep. No. 16.

FRDA Reports and Memos: A complete list of FRDA publicationscovering a variety of forest management interpretations isavailable from: Communications Assistant, Research Branch,Ministry of Forests, 31 Bastion Sq., Victoria, B.C. V8W 3E7; orfrom: Pacific Forestry Centre, 506 West Burnside Rd., Victoria,B.C. V8Z IM5.

Haeussler, S., D. Coates, and J. Mather. 1990. Autecology of commonplants in British Columbia. B.C. Min. For. and For. Can., Victoria,B.C. FRDA Rep. No. 158.

Hopwood, D. 1991. Principles and practices of new forestry: a guide forBritish Columbians. B.C. Min. For., Victoria, B.C. Land Manage.Rep. No. 71.

Other References

A • 7

Lavender, D.P., R. Parish, C.M. Johnson, G. Montgomery, A. Vyse, R.A.Willis, and D. Winston. 1990. Regenerating British Columbia’sforests. For. Can. and B.C. Min. For., Univ. B.C. Press, Vancouver,B.C.

Lewis, T., W.W. Carr, and Timber Harvesting Subcommittee. 1989.Developing timber harvesting prescriptions to minimize sitedegradation: interior sites. B.C. Min. For., Victoria, B.C. LandManage. Handb. Field Guide Insert.

Lewis, T. and the Timber Harvesting Subcommittee. 1991. Developingtimber harvesting prescriptions to minimize site degradation. B.C.Min. For., Victoria, B.C. Land Manage. Rep. No. 62.

Mathews, J.D. 1989. Silvicultural systems. Clarendon Press, Oxford,U.K.

Scagel, R. and R. Evans (editors). 1989. Reforestation in the MountainHemlock zone: history and current status. B.C. Min. For. and For.Can., Victoria, B.C. FRDA Workb. No. 03.

Silviculture Interpretations Working Group. 1993. Correlated guidelinesfor tree species selection (1st approx.) and stocking standards (2ndapprox.) for the ecosystems of British Columbia. B.C. Min. For.and For. Can., Victoria, B.C.

Trowbridge, R., B. Hawkes, A. Macadam, and J. Parminter. 1987. Fieldhandbook for prescribed fire assessments in British Columbia:logging slash fuels. B.C. Min. For. and For. Can., Victoria, B.C.FRDA Handb. No. 001.

Trowbridge, R.L. and A. Macadam (compilers and editors). 1983.Prescribed fire: Forest Soils Symp. Proc., March 2-3, 1982. B.C.Min. For., Victoria, B.C. Land Manage. Rep. No. 16.

Weetman, G.F., E. Panozzo, M. Jull, and K. Marek. 1990. An assessmentof opportunities for alternative silvicultural systems in the SBS,ICH, and ESSF biogeoclimatic zones of the Prince Rupert ForestRegion. B.C. Min. For., Smithers, B.C. Contract rep.

3 Wildlife Interpretation Reports

B.C. Coastal Fisheries/Forestry Guidelines Technical Committee. 1992.British Columbia coastal fisheries/forestry guidelines. 3rd ed. B.C.Min. For., B.C. Min. Environ., Lands, Parks, Dep. Fish. Oceans,and COFI, Victoria, B.C.

B.C. Interior Fish, Forestry and Wildlife Guidelines Committee. 1993.Interior fish, forestry and wildlife guidelines. B.C. Min. For., B.C.Min. Environ., Lands, Parks, Dep. Fish. Oceans, and COFI,Victoria. B.C. Draft rep.

Other References

A• 8

B.C. Ministry of Environment and Ministry of Forests. 1990. Proceduresfor environmental monitoring in range and wildlife habitatmanagement. Victoria, B.C.

B.C. Ministry of Forests and Ministry of Environment. 1992. Guidelinesto maintain biological diversity in coastal forests. Victoria, B.C.Draft rep.

__________. 1993. Guidelines for maintaining biodiversity during juvenilespacing. Victoria, B.C. Draft FRDA rep.

B.C. Wildlife Act. 1982. Queen’s Printer, Victoria, B.C.

Bunnell, F.L., D.K. Daust, W. Klenner, L.L. Kremsater, and R.K.McCann. 1991. Managing for biodiversity in forested ecosystems.Report to the forest sector of the Old Growth Strategy. B.C. Min.For., Victoria, B.C. Unpubl. rep.

Campbell, R.W., N.K. Dawe, I. McTaggart-Cowan, J.M. Cooper, G.W.Kaiser, and M.C.E. McNall. 1990. The birds of British Columbia.Vol. 1. Royal B.C. Museum, Victoria, B.C.

Cichowski, D.B. and A. Banner. 1993. Management strategy and optionsfor the Tweedsmuir-Entiako caribou winter range. B.C. Min. For.,Victoria, B.C. Land Manage. Rep. No. 83. In press.

Fenger, M., T. Lea, B. Fuhr, and D. Demarchi. 1990. Wildlife habitatmap, Skeena North. Map at 1:500 000. B.C. Min. Environ.,Victoria, B.C.

Habitat Monitoring Committee. 1990. Procedures for environmentalmonitoring in range and wildlife habitat management. Draft ed.version 4.1. B.C. Min. Environ., Lands, Parks and B.C. Min. For.,Victoria, B.C.

Hamilton, T. [1993]. Integrating coastal grizzly bear habitat andsilviculture in the Vancouver Forest Region. B.C. Min. Environ.,Lands, Parks, Victoria, B.C. (in prep.).

Hamilton, A.N., E.L. Richardson, and C.A. Bryden.[1994]. Coastal grizzlybear fieldbook: integration of grizzly bear habitat and forestry incoastal B.C. (in prep.).

Hansen, A.J., T.A. Spies, F.J. Swanson, and J.L. Ohmann. 1991.Conserving biodiversity in managed forests. BioScience 41(6):382-392.

Harris, L.D. 1984. The fragmented forest: island biogeography theory andthe preservation of biotic diversity. Univ. Chicago Press, Chicago,Ill.

Hunter, M.L. Jr. 1990. Wildlife, forests, and forestry: principles ofmanaging forests for biological diversity. Prentice Hall, Inc.,Englewood Cliffs, N.J.

Other References

A • 9

Klenner, W. 1991. Pre-harvest silvicultural prescriptions to protect andmaintain wildlife habitat. B.C. Min. For., Vancouver, B.C. Unpubl.contract rep.

Lloyd, R. 1993. Wildlife interpretations for the SBS, ESSF and ICHbiogeoclimatic zones of the Prince Rupert Forest Region. B.C. Min.For., Smithers, B.C. Unpubl. contract rep.

Meidinger, D. and J. Pojar (compilers and editors). 1991. Ecosystems ofBritish Columbia. B.C. Min. For.,Victoria, B.C. Special ReportSeries 6.

Old Growth Strategy Project. 1992. Towards an old growth strategy:public review draft. B.C. Min. For., Victoria, B.C.

Pojar, J. 1985. Vegetation and ungulate habitat in the Gladys LakeEcological Reserve, northern British Columbia. B.C. Min. For.,Victoria, B.C. Res. Rep. RR85009-PR.

Radcliffe, G., G. Porter, B. Bancroft, and C. Cadrin. 1993. Biodiversity ofthe Prince Rupert Forest Region. B.C. Min. For., Victoria, B.C.Land Manage. Rep. No. 82. In press.

Ramsay, L.R. 1992. Methodology for monitoring wildlife diversity in B.C.forests: proceedings of a workshop. B.C. Min. Environ., WildlifeBr., Victoria, B.C.

Steventon, J.D. [1993]. Biodiversity and forest management in the PrinceRupert Forest Region: a discussion paper. B.C. Min. For., Victoria,B.C. Land Manage. Rep. (in prep.).

Wildlife Tree Committee of B.C. 1993. Draft provincial harvestingguidelines for the management and maintenance of wildlife trees.B.C. Min. For., Min. Environ., Lands, Parks, and Workers’Compensation Board of B.C., Victoria, B.C.

4 Plant Identification References

Royal B.C. Museum, publications in natural history. Handbook series foridentifying plant species of common plant families. Queen’sPrinter, Victoria, B.C.

Coupé, R., C.A. Ray, A. Comeau, M.V. Ketcheson, and R.M. Annas(compilers). 1982. A guide to some common plants of the Skeenaarea, British Columbia. B.C. Min. For., Victoria, B.C. LandManage. Handb. No. 4.

Douglas, G.W., A. Ceska, and G.G. Ruyle. 1983. A floristic bibliographyfor British Columbia. B.C. Min. For., Victoria, B.C. Land Manage.Rep. No. 15.

Other References

A• 10

Douglas, G.W., G.B. Straley, and D. Meidinger. 1989. The vascular plantsof British Columbia. Part 1. Gymnosperms and Dicotyledons(Aceraceae through Curcurbitatceae). B.C. Min. For., Victoria, B.C.Special Report Series 1.

__________. 1990. The vascular plants of British Columbia. Part 2.Dicotyledons (Diapensiaceae through Portulaceae). B.C. Min. For.,Victoria, B.C. Special Report Series 2.

__________. 1991. The vascular plants of British Columbia. Part 3.Dicotyledons (Primulaceae through Zygophyllaceae) andPteridophytes. B.C. Min. For., Victoria, B.C. Special Report Series 3.

__________. 1993. The vascular plants of British Columbia. Part 4.Monocotyledons. B.C. Min. For., Victoria, B.C. Special ReportSeries 4. In press.

Hitchcock, C.L. and A. Cronquist. 1973. Flora of the Pacific Northwest.An illustrated manual. Univ. Wash. Press, Seattle, Wash.

Ireland, R.R., G.R. Brassard, W.B. Schofield, and D.H. Vitt. 1987.Checklist of the mosses of Canada II. Lindbergia 13:1-62.

Klinka, K., V.J. Krajina, A. Ceska, and A.M. Scagel. 1989. Indicatorplants of coastal British Columbia. B.C. Min. For. and For. Can.FRDA. Univ. B.C. Press, Vancouver, B.C.

MacKinnon, A., J. Pojar, and R. Coupé (editors). 1992. Plants of northernBritish Columbia. B.C. Min. For. and For. Can. FRDA. Lone PinePubl., Edmonton, Alta.

Meidinger, D. 1988. Recommended vernacular names for common plantsof British Columbia. B.C. Min. For., Lands. Res. Rep.RR87002-HQ.

Pojar, J., R. Love, D. Meidinger, and R. Scagel. 1982. Some commonplants of the Sub-Boreal Spruce zone. B.C. Min. For., Victoria, B.C.Land Manage. Handb. No. 6.

Porter, D.L. 1990. Willow species of disturbed sites in the Sub-BorealSpruce zone in north-central British Columbia. B.C. Min. For. andFor. Can., Victoria, B.C. FRDA Handb. No. 004.

Roberts, A. 1983. A field guide to the sedges of the Cariboo ForestRegion, British Columbia. B.C. Min. For., Victoria, B.C. LandManage. Rep. No. 14.

Schofield, W.B. 1992. Some common mosses of British Columbia. RoyalB.C. Museum, Victoria, B.C. Handb. No. 28.

Stotler, R. and B. Crandall-Stotler. 1977. A checklist of the liverwortsand hornworts of North America. The Bryologist 80:405-428.

Vitt, D.H., J.E. Marsh, and R.B. Bovey. 1988. Mosses, lichens, and fernsof northwest North America: a photographic field guide. Lone PinePubl., Edmonton, Alta.

Other References

A • 11

APPENDIX 2. Correlation between old and newbiogeoclimatic and site units

These tables provide old and new biogeoclimatic and site unit symbolsand numbers. Table A2.1 contains biogeoclimatic names used in Pojar etal. 1988 and in publications previous to 1988. Tables A2.2 - 2.5 providesite unit numbers used in Silviculture Manual Insert A (1990) and inpublications previous to 1990.

TABLE A2.1. Biogeoclimatic units for all zones and their previous equivalents

Current Pojar et al. 1988 Pre-1988BGC unit

AT AT AT

BWBSdkl BWBSa1 BWBSa2BWBSdk2 BWBSe BWBSe

CWHvh2 CWHvh CCPH, CWHd, CWHhmCWHvm1 CWHvm1 CWHi1, CWHb1CWHvm2 CWHvm2 CWHi2, CWHb2CWHwm CWHwm CWHjCWHws1 CWHws1 CWHf1CWHws2 CWHws2 CWHf2, CWHi3

ESSFmc ESSFk ESSFkESSFmk ESSF1 ESSF1ESSFwv ESSFi ESSFi

ICHmc1 ICHmc2 ICHg1ICHmc1a ICHmc2 ICHg1aICHmc2 ICHmc3 ICHg2, g3ICHvc ICHvc ICHg4ICHwc ICHvc ICHg5

MHmm1 MHa MHa, MHdMHmm2 MHb MHb, MHeMHwh1 MHc1 MHc1

SBPSmc SBPSmc SBSa2

SBSdk SBSdk SBSdSBSmc2 SBSmc SBSe1

Correlation

A• 12

APPENDIX 2. (Continued)

TABLE A2.2. Site units in the BWBS and SBS zones and their previous equivalents

Currentsite unit BWBSdk1 BWBSdk2 SBPSmc SBSdk SBSmc2

Previous BWBS and SBS equivalents

01 e/01a a/01b SBSa2/01,03b d/01b el/01,04b

e/01b dk2/01c SBPSmc/01c dk/01c mc2/01c

dk1/01c

02 e/02,03 a/02 SBSa2/02 d/02 e1/02,03e/02,03 dk2/02 SBPSmc/02 dk/02 mc2/02dk 1 /02

03 nped a/04 SBSa2/04 d/03 e1/05e/06 dk2/04,09 SBPSmc/03 dk/03 mc2/03dk1/03

04 a/05 a/07 SBSa2/05 d/06 nae/07 dk2/05,06 SBPSmc/04 dk/05dk1/04

05 npe npe SBSa2/06 d/07 e1/06npe dk2/07 SBPSmc/05 dk/06dk1/05

06 npe a/05,06 SBSa2/07 d/08 e1/07e/08 dk2/08,10 SBPSmc/06 dk/08 mc2/07dk1/06

07 npe a/08 SBSa2/08 d/09 e1/10npe dk2/11 SBPSmc/07 dk/09 mc2/04dk1/07

08 a/06 a/09 na d/10 nae/10 dk2/12 dk/10dk1/08

09 a/07 na na d/12 e1/08e/09 dk/11 mc2/09dk 1 /09

10 a/09 na na d/11 e1/09e/12 dk/12 mc2/10dk1/10

11 e/08,10 na na na nae/11,13dk1/11

12 nae na na na e1/11mc2/ 12

31 npe npe npe npe npe

32 npe npe npe npe na

81 npe a/03 na d/04 nadk2/03 dk/04

82 na na d/05 nadk/07

a As per Trowbridge et al. 1983.b As per Silviculture Manual Insert 11, April 1989.c As per Silviculture Manual Insert A, Appendix 11 (1990).d No previous equivalent (npe).e Site unit does not occur in this biogeoclimatic unit in the PRFR (na).

Correlation

A • 13


TABLE A2.3. Site units in the CWH zone and their previous equivalents

Currentsite unit CWHvh2 CWHvm1 CWHvm2 CWHwm CWHws1 CWHws2

Previous CWH equivalents

01 hm/0 la i1/01a i2/01a j/01a f1/01a f2/01a

vh2/01b vm1/01b vm2/01b wm/01b ws1/01b ws2/01b

02 hm/02 i1/02 npe j/02,03 fl/02(1) npevh2/02 vm1/02 npe wm/02 ws1/02 npe

03 hm/03 il/03 i2/02 j/04 fl/02 f2/02vh2/03 vm1/03 vm2/02 wm/03 ws1/03 ws2/02

04 hm/05 il/04(1) na j/06 f l/03 f2/03vh2/04 vm1/04 wm/04 wsl/04 ws2/03

05 hm/06(2) i1/04(l) i2/04 j/05 npe npevh2/05 vm1/05 vm2/03 ws1/05

06 hm/06,07 i1/04 i2/04 npe f l/04 f2/04vh2/06 vm1/06 vm2/04 wm/06 ws1/06 ws2/04

07 hm/08 na na npe f l/05 npevh2/07 wm/07 ws1/07

08 hm/09.1 i1/05 i2/05 npe fl/05(1) npevh2/08 vm1/08 vm2/05 wm/09 ws1/08

09 hm/09.2 i1/06 i2/03 j/07 npe npevh2/09 vml/09 vm2/06 wm/10 ws1/09

10 npec npe i2/06 j/08 f l/07 npevh2/10 vm1/10 npe wm/11 ws1/11

11 hm/11 npe npe na fl/06 npevh2/11 vm1/11 ws1/10

12 hm/12 npe na na na navh2/12

13 hm/10 npe na na na navh2/13 vm1/13

14 hm/04 i1/07 na na na navh2/17 vm1/12

15 hm/04 na na na na na02/18

16 hm/04 na na na na navh2/19

17 npe na na na na navh2/20

18 npe na na na na navh2/21

19 npe na na na na na

31 hm/13 npe npe npe npe npevh2/ 14

32 hm/14 npe npe npe npe npevh2/15 wm/12

33 hm/15 na na na na navh2/16

51 nad npe npe npe na npewm/08

a As per Silviculture Manual Insert 11, April 1989.b As per Silviculture Manual Insert A, Appendix II (1990).c No previous equivalent (npe).d Site unit does not occur in this biogeoclimatic unit in the PRFR (na).

Correlation

A• 14


TABLE A2.4 Site units in the ESSF and MH zones and their previous equivalents

Currentsite unit ESSFmc ESSFmk ESSFwv MHmm MHwh1

Previous ESSF and MH equivalents

01 k/01a l/01a i/01a MH/01a MH/01a

mc/01b mk/01b wv/01b mm/01b wh1/0102 k/02 l/02 i/02 npe npe

mc/02 mk/02 wv/02 mm/02 wh1/0203 k/03 l/03 i/03 npe npe




mc/06 mk/06 wv/06 mm/06 wh1/0607 k/07 l/06 i/07 MH02 MH/02

mc/07 mk/07 wv/07 mm/07 wh1/0708 k/08 nad npe MH04 MH/04

mc/09 wv/08 mm/08 wh1/0809 k/10 na i/08 MH03 MH03

mc/08 wv/09 mm/09 wh1/0910 k/09 na na na na

mc/1031 npec npe npe npe npe

51 npe npe npe npe na

a As per Silviculture Manual Insert 11, April 1989.b As per Silviculture Manual Insert A, Appendix II (1990).c No previous equivalent (npe).d Site unit does not occur in this biogeoclimatic unit in the PRFR (na).

Correlation

A • 15


TABLE 22.5. Site units in the ICH zone and their previous equivalents

Currentsite unit ICHmc1 ICHmc1a ICHmc2 ICHvc ICHwc

Previous IC H equivalents

01 g1/01,03a g1a/01,02a g2/01,03a g4/01a npemc1/01b mc1a/01b g3/01,03a vc1/01b

mc2/01b

02 g1/02 g1a/03 g2/02 g4/03 npemc1/02 mc1a/02 g3/02 vc1/02

mc2/0203 g1/04 g1 a/04 g2/04 g4/04 npe

mc1/03 mc1a03 npe vc1/03mc2/04

04 g1/05 na g2/05 g4/06 npemc1/04 g3/04.1 vc1/06

mc2/0505 g1/07 na npe g4/10 npe

mc1/05 g3/05 vc1/05mc2/06

06 g1/06 na g2/07 g4/05 npemc1/06 g3/11 vc1/07

mc2/0707 nac na g2/06 na npe

g3/06mc2/09

08 na na npe na npeg3/07mc2/08

09 na na na na na

31 nped na npe g4/09 npevc1/09

32 na na npe na npe

51 na na npe g4/07 npeg3/08 vc1/04mc2/50

52 na na npe g4/08 npeg3/09 vc1/08mc2/51

53 na na npe na nag3/10mc2/52

54 na na npe na nag3/04.2mc2/03

a As per Silviculture Manual Insert 11, April 1989; note that the old ICHg2 and g3 have nowbeen combined into one variant (ICHmc2).

b As per Silviculture Manual Insert A, Appendix II (1990).c Site unit does not occur in this biogeoclimatic unit in the PRFR (na).d No previous equivalent (npe).

Correlation

A• 16

APPENDIX 3. Tree species codes and symbolsTreecodea Common name Scientific name Symbol

Acb balsam poplar Populus balsamifera ssp.balsamifera

Act black cottonwood Populus balsamifera ssp.trichocarpa

At trembling aspen Populus tremuloides

Ba amabilis fir Abies amabilis

Bl subalpine fir Abies lasiocarpa

Cw western redcedar Thuja plicata

Dr red alder Alnus rubra

Ep paper birch Betula papyrifera

Fd Douglas-fir Pseudotsuga menziesii

Jr Rocky Mountain Juniperus scopulorumjuniper

a Tree species codes follow B.C. Ministry of Forests, Inventory Branch standards.

Tree Codes and Symbols

A • 17


Treecode Common name Scientific name Symbol

Hm mountain hemlock Tsuga mertensiana

Hw western hemlock Tsuga heterophylla

Lt tamarack Larix laricina

Pa whitebark pine Pinus albicaulis

Pl lodgepole/ Pinus contortashore pine

Sb black spruce Picea mariana

Sw white spruce Picea glauca

Sxw hybrid white spruce Picea glauca xengelmannii

Ss Sitka spruce Picea sitchensisSxs Roche spruce Picea sitchensis x glaucaSx Roche spruce Picea glauca x sitchensis

x engelmannii (P. x lutzii)

Yc yellow-cedar Chamaecyparisnootkatensis

Tree Codes and Symbols

A• 18

APPENDIX 4. Ecoregion classification in thePRFRa

There are 4 ecoprovinces, 16 ecoregions, and 29 ecosections in thePRFR (Figure A4.1 ; Table A4.1).

1.1 Coast and Mountains Ecoprovince

This ecoprovince extends from coastal Alaska to coastal Oregon (FigureA.4.1). In the PRFR it includes the windward side of the CoastMountains and consists of the large coastal mountains, a broad coastaltrough, and the associated lowlands, islands, and continental shelf. Themajor climate processes involve the arrival of frontal systems from thePacific Ocean and the subsequent lifting of those systems over the coastalmountains. In the PRFR, the Coast and Mountains Ecoprovince isdivided into five ecoregions containing nine ecosections.

The Coastal Gap Ecoregion contains somewhat rounded mountainswith lower relief than those to either the north or south. Valley sides arerugged and steep, and, because of their lower relief, allow considerablemoisture to enter the interior of the province. This ecoregion includes theHecate Lowland Ecosection, an area of low relief consisting of islands,channels, rocks, and lowlands adjacent to Hecate Strait, and the KitimatRanges Ecosection, an area of subdued, yet steep-sided mountains justwest of the Hecate Lowland.

The Hecate Continental Shelf Ecoregion is a shallow mantle arealocated between the Queen Charlotte Islands and the mainland coast. Itincludes the Dixon Entrance Ecosection and the Hecate StraitEcosection, which both have only a few offshore islets in the PRFR.

The Nass Basin Ecoregion is an area of low relief located within theCoast Mountains. It is influenced by mild, coastal weather systems, aswell as the cold arctic systems. This ecoregion is not subdivided intoecosections.

The Nass Ranges Ecoregion is a mountainous area west of the Kitimatranges. Its climate is transitional between the coastal and interiorregimes. This ecoregion is not subdivided into ecosections.

The Northern Coastal Mountains Ecoregion is a rugged, largely ice-capped mountain range that rises abruptly from the coast. It includes theAlaska Panhandle Mountains Ecosection, an area of wet ruggedmountains, primarily occurring in Alaska; the Alsek RangesEcosection, an area of isolated, very rugged ice-capped mountains thatlie in the curve of the Gulf of Alaska; and the Boundary RangesEcosection, a large block of rugged, ice-capped, granitic mountains thatare dissected by several major river valleys.

a Contributed by D.A. Demarchi.

Ecoregions

A • 19

FIGURE A4.1. Map showing the ecoprovinces, ecoregions, andecosections in the Prince Rupert Forest Region. Refer toTable A4.1 for explanation of ecosection abbreviations.

Ecoregions

A• 20

TABLE A4.1. Ecoregion classification for the Prince Rupert ForestRegion

Ecodomain Ecodivision Ecoprovince Ecoregion Ecosection Code

Humid Humid Coast and Coastal Gap Hecate Lowland HELTemperature Maritime and Mountains Kitimat Ranges KIR

Highlands Hecate Dixon Entrance DIEContinental Shelf Hecate Strait HES

Nass Basin (Nass Basin) NABNass Ranges (Nass Ranges) NAR

Northern Coastal Alaska Panhandle APMMountains Mountains

Alsek Ranges ALRBoundary Ranges BOR

Humid Central Bulkley Ranges (Bulkley Ranges) BURContinental interiorHighlands Fraser Plateau Bulkley Basin BUB

Nazko Upland NAUNechako Upland NEU

Sub-Boreal Fraser Basin Babine Upland BAUInterior

Omineca Eastern Skeena ESMMountains Mountains

Skeena Northern Skeena NSMMountains Mountains

Southern Skeena SSMMountains

Polar Sub-Arctic Northern Kluane Plateau Tatshenshini Basin TABHighlands Boreal

Mountains Liard Basin Liard Plain LIP

Northern Eastern Muskwa EMRCanadian Rocky RangesMountains

Northern Cassiar Ranges CARMountains and Kechika KEMPlateaus Mountains

Southern Boreal SBPPlateauStikine Plateau STPTeslin Plateau TEPTuya Range TUR

St. Elias Icefield Ranges ICRMountains

Yukon - Stikine Tagish Highland TAHHighlands Tahltan Highland THH

Ecoregions

A • 21

1.2 Central Interior Ecoprovince

This ecoprovince lies to the east of the Coast Mountains, between theFraser Basin and the Thompson Plateau (Figure A4.1). In the PRFR, itmostly contains the southern Nechako Plateau and some of the mountainranges on the east side of the coastal mountains. The area has a typicallysub-continental climate, with warm summers and the maximumprecipitation occurring in late spring or early summer. In the PRFR, thisecoprovince contains two ecoregions and four ecosections.

The Bulkley Ranges Ecoregion is a narrow mountain area locatedleeward of the rounded Kitimat Ranges. Moist Pacific air invades thisarea through numerous low passes, while cold arctic air frequently stallsalong its eastern boundary. This ecoregion is not subdivided intoecosections.

The Fraser Plateau Ecoregion is a broad, rolling plateau that includesseveral shield volcanoes and a small portion of the leeward side of theKitimat Ranges. It includes the Bulkley Basin Ecosection, a broadlowland area, with a rain shadow climate in the north; the NazkoUpland Ecosection, a flat upland area, with increased precipitationlocated in the north-northeast; and the Nechako Upland Ecosection, arolling upland area with several high shield volcanoes withwell-developed alpine areas.

1.3 Sub-Boreal Interior Ecoprovince

This ecoprovince lies to the east of the Coast Mountains, to the west ofthe Interior Plains, and to the north of the Fraser Plateau (Figure A4.1).Prevailing winds bring Pacific air over the Coast Mountains to the areaby way of the low Kitimat Ranges or the higher Boundary Ranges. Muchof the area is in a rain shadow. In this region, the Sub-Boreal Interiorecoprovince is divided into three ecoregions and four ecosections.

The Fraser Basin Ecoregion consists of a broad, flat lowland with lowridges, and several large lakes in the depressions. In the PRFR, itconsists only of the Babine Upland Ecosection, a rolling upland withlow ridges, and large lakes in the depressions.

In the PRFR, the Omineca Mountains Ecoregion consists of theEastern Skeena Mountains Ecosection, an area of high, isolatedmountain groups and wide intermountain plains in the rain shadow ofthe Skeena Mountains Ecoregion.

The Skeena Mountains Ecoregion is the area of rugged ranges west ofthe Omineca Mountains. It includes the Northern Skeena MountainsEcosection, an area of rugged mountains and narrow, deep valleys withheavy snow; and the Southern Skeena Mountains Ecosection, anarea of wide valleys and isolated mountain ranges to the south.

1.4 Northern Boreal Mountains Ecoprovince

This ecoprovince lies east of the Boundary Ranges of the Coast Mountains,west of the Interior Plains, and south of the Yukon Territory, in thenortheastern part of the PRFR (Figure A4.1). This area generally consists

Ecoregions

A• 22

of mountains and plateaus separated by wide valleys and lowlands.Prevailing westerly winds bring Pacific air over the high St. EliasMountains and Boundary Ranges to the area. This area is characterizedby rain shadow effects that can cause some areas to be very dry. In thePRFR, it consists of 6 ecoregions and 12 ecosections.

The Kluane Plateau Ecoregion is an area of broad smooth slopes, witha wide intermountain plain. In British Columbia, this area is representedby the Tatshenshini Basin Ecosection, an area with rounded,subdued mountains and a wide valley, leeward of the rugged Boundaryand St. Elias ranges. In spite of its proximity to the Pacific Ocean, it hasa typically cold boreal climate.

The Liard Basin Ecoregion is an extensive area of lowland to rollingupland that extends from northern British Columbia into the Yukon. Inthe PRFR it consists of the Liard Plain Ecosection, a broad, rollinglowland area with a cold boreal climate.

The Northern Canadian Rocky Mountains Ecoregion is an area ofhigh, rugged mountains that rise abruptly from the Interior Plain to theeast. In the PRFR, it is represented by only the Eastern MuskwaRanges Ecosection, an area with rugged mountains, many of which areice-capped.

The Northern Mountains and Plateaus Ecoregion is a large areawith a complex of lowlands, rolling and high plateaus, and ruggedmountains, with a dry boreal climate. It includes the Cassiar RangesEcosection, a broad band of mountains extending from the southeastcorner of the ecoregion to the northeast corner; the Kechika MountainsEcosection, an area with high mountains, but low, wide valleys in therain shadow of the Cassiar Ranges to the west; the Southern BorealPlateau Ecosection, several deeply incised plateaus; the StikinePlateau Ecosection, a plateau area with variable relief, from lowlandto rolling alpine; the Teslin Plateau Ecosection, a rolling plateau area,lying in a distinct rain shadow; and the Tuya Range Ecosection, anarea of extensive rolling alpine.

The St. Elias Mountains Ecoregion is a bold ice-capped mountain arealying leeward of the Gulf of Alaska. It is represented by the IcefieldRanges Ecosection, an ice-capped, rugged mountain area that is thesouthern extension of the St. Elias Mountains.

The Yukon - Stikine Ecoregion is a transitional mountain area lyingbetween the rugged coastal mountains to the west and the subduedplateaus to the east. It includes the Tagish Highland Ecosection, atransitional mountain area that faces northeast, with all streamsdraining into the upper Yukon River system; and the Tahltan HighlandEcosection, a transitional mountain area with several large valleysexposed to the coast.

Ecoregions

A • 23

APPENDIX 5. Sample ecological classificationreconnaissance plot form

Plot Form

A• 24


Plot Form

A • 25

APPENDIX 6. Relative and actual soil moisturerelationshipsa

In this guide we use both relative and actual classes of soil moistureregime to characterize and describe site units. On the edatopic gridspresented for each biogeoclimatic unit in Chapter 5, relative soil moistureregime (RSMR) is depicted on the left-hand vertical axis and actual soilmoisture regime (ASMR) on the right-hand vertical axis.

RSMR is useful at the field level for assessing the relative amount of soilmoisture available for plant growth within a subzone using site and soilcharacteristics (see Appendix 7).

ASMR is useful for a more quantitative comparison of soil moistureavailability among subzones. A water-balance approach is used todescribe the average amount of soil water actually available for plants.ASMR classes are defined in Table 6A.1 and the relationships betweenRSMR and ASMR for 16 subzones in the PRFR are presented in Table6A.2.

Table 6A.1. Classification of actual soil moisture regimes

Differentiating criteria Class

Rooting-zone groundwater absent during the growing seasonWater deficit occurs (soil-stored reserve water is used up and droughtbegins if current precipitation is insufficient for plant needs)

Deficit > 3 months but _< 5 months (AET/PET <_ 60 but > 40%) very dryDeficit > 1.5 months but <_ 3 months (AET/PET <_ 90 but > 60%) moderately dryDeficit > 0 but <_ 1.5 months (AET/PET > 90%) slightly dry

No water deficit occursUtilization (and recharge) occurs (current need for water freshexceeds supply and soil-stored water is used)No utilization (current need for water does not exceed supply; moisttemporary groundwater table may be present)

Rooting-zone groundwater present during the growing season(water supply exceeds demand)

Groundwater table > 30 cm deep very moistGroundwater table > 0 but <_ 30 cm deep wetGroundwater table at or above the ground surface very wet

a After Klinka et al. (1989) and Wang et al. [1992].

SMR Relationships

A• 26

Table 6A.2. Relative and actual soil moisture relationships

Relative SMRa

Actual SMRb

Biogeo-climatic 0 1 2 3 4 5 6 7subzone

MHwh SD SD F F F M VM W

MHmm SD SD F F F M VM W

CWHvh SD SD F F M VM W W

CWHwm SD SD SD F F M VM W

CWHvm MD SD SD F F M VM W

CWHws VD MD MD SD F M VM W

ICHvc MD SD SD F F M VM W

ICHwc MD MD SD F F M VM W

ICHmc VD MD SD SD F M VM W

ESSFwv MD SD SD F F M VM W

ESSFmc VD MD SD SD F M VM W

ESSFmk VD VD MD SD F M VM W

SBSmc VD MD MD SD F M VM W

SBSdk VD MD MD SD SD F M-VM W

BWBSdk VD MD MD SD SD F M-VM W

SBPSmc VD VD VD MD SD F M-VM W

a 0 - very xeric, 1 - xeric, 2 - subxeric, 3 - submesic, 4 - mesic, 5 - subhygric, 6 - hygric, 7- subhydric.

b VD - very dry, MD - moderately dry, SD - slightly dry, F - fresh, M - moist, VM - verymoist, W - wet.

SMR Relationships

A • 27

APPENDIX 7. Soil moisture regime identificationkeya

This key is to assist the user in identifying the soil moisture regimeusing readily observable environmental features. It should be appliedwith caution on steep, south slopes of drier subzones. In such cases, thesoil moisture regime class may be one class drier. The soil moistureregime classes 0 - 7, shown in the key, correspond to the terms very xeric(0) to subhydric (7 ).b

Category Definition

Ridge crest Height of land; usually convex slope shape.

Upper slope The generally convex-shaped, upper portion of a slope.

Middle slope The portion of a slope between the upper and lowerslopes; the slope shape is usually straight.

Lower slope The area towards the base of a slope; the slope shape isusually concave; it includes toe slopes, which aregenerally level areas located directly below andadjacent to the lower slope.

Flat Any level area (excluding toe slopes); the surface shapeis generally horizontal with no significant aspect.

Alluvium Post-glacial, active floodplain deposits along rivers andstreams in valley bottoms; usually a series of lowbenches and channels.

Depression Any area that is concave in all directions; usually atthe foot of a slope or in flat topography.

Soil depth Depth from the mineral soil surface to a root-restrictinglayer such as bedrock, or strongly compacted or stronglycemented materials (e.g., “hardpan”).

Gleyed Describes soils that have poor drainage and may begleyed or mottled; permanently saturated (gleyed) soilsare dull yellowish, blue, or olive in colour; soils thathave orange-coloured mottles indicate a fluctuatingwater table.

Coarse texture Sandyc with >35% volume of coarse fragments orloamyc with >70% volume of coarse fragments.

Fine texture Siltyc or clayeyc with <20% coarse fragment volume.

a Adapted from Braumandl and Curran (1992), Lloyd et al. (1990), and Green et al.(1984).

b 0 - very xeric, 1 - xeric, 2 - subxeric, 3 - submesic, 4 - mesic, 5 - subhygric, 6 - hygric, 7- subhydric.

c Sandy - LS, S; loamy - SL, L, SCL; clayey - SiCL, CL, SC, SiC, C; silty - SiL, Si (seeAppendix 11 for soil texture determination).

Soil Moisture ID

A• 28

A key to the identification of soil moisture status

Soil Moisture ID

A • 29

a Generally moister if aspect is N or NE.b Generally drier if aspect is S or SW.

APPENDIX 8. Soil nutrient regime identificationtablea

Soil nutrient regime indicates, on a relative scale, the available nutrientsupply for plant growth (Pojar et al. 1987). The soil’s nutrient regimeintegrates many environmental and biotic parameters that, incombination, determine the relative amounts of available nutrients. Theaim of the assessment is to derive an estimate of the available nutrientsupply for a site, which will characterize it relative to all other sitesoccurring within the biogeoclimatic subzone or variant. The fieldassessment is a qualitative evaluation of site characteristics. Aquantitative assessment is not usually possible because critical nutrientconcentrations are unknown for most plant species. Laboratory analysisis also expensive and time consuming.

Common site factors and their relative contribution to soil nutrientregime are shown in the conceptual key on the next page. All factorsshould be evaluated to determine the site nutrient class. Use of the tableinvolves considering the relative levels of all factors. For example, a siteon an upper slope with very coarse soil (sandy texture, 70% coarsefragments [CFs]) and granitic rock fragments would be classified as verypoor for soil nutrients. In contrast, a site on a lower slope withfine-textured soil (clayey texture, 10% CFs) and dark-coloured uppermineral horizons would be classified as very rich. As many factors aspossible should be evaluated because a limiting factor may becompensated for by the effect of other factors. For example, a site withvery coarse soil (sandy texture, 80% CFs) on a lower slope could beclassified as nutrient-rich if continuous seepage was present in the soilprofile.

a Adapted from Braumandl and Curran (1992).

Soil Nutrient ID

A• 30

A • 31

Soil Nutrient ID

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Landform ID

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APPENDIX 9. Landform identification key

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Landform ID

A • 33

APPENDIX 10. Key to common rock types of the PRFRa

Rock Type ID

A• 34

a Adapted from Braumandl and Curran (1992) and Lloyd et al. (1990)

APPENDIX 11. Soil texturing keya

Soil texture is the relative proportion of various “size fractions” of soil.

The coarse fragment fraction consists of particles >2 mm in diameter(for non-spherical particles, measure second-largest dimension). It isdivided into three size classes: gravels (2 - 75 mm), cobbles (75 - 250mm), and stones (>250 mm). Coarse fragments are estimated visually asa percentage of the whole soil (by volume): %stones + %cobbles +%gravels + %fine fraction = 100% (total soil).

The fine fraction consists of particles <2 mm in diameter. Again, the finefraction is divided into three size classes: sand, silt, and clay. The relativeproportion of fine fraction particles (sand, silt, and clay) is estimatedthrough the use of their unique properties of “feel”:

Sand always felt as individual grains (visible when soil issmeared on finger)

Fine sand dry - similar to silt;wet - not soapy or slippery, stiffer than silt (likegrinding compound or fine sandpaper)

Silt dry - feels floury;wet - slippery or soapy, slightly sticky

Clay dry - forms hard lumps;moist - plastic (like plasticine);wet - very sticky.

Most soils are a mixture of sand, silt, and clay, so the degree ofgraininess, soapiness, or stickiness will vary depending on how much ofeach particle size is present. As the amount of clay increases, soilparticles bind together better and form stronger casts, and they can berolled into thinner, stronger “worms”. As sand and silt content increase,the soil binding strength decreases and only weak to moderately strongcasts and worms can be formed. The various classes of soil texture,defined on the textural triangle in the accompanying figure, are named bya combination of the dominant particle sizes; the term loam means arelatively even mix of the three.

The field determination of soil texture is subjective and can only be doneconsistently with training and experience. Most particles >2 mm in sizemust be removed to enable precise assessment of soil texture. A small 2mm screen helps. The field tests (outlined on the following page and usedin sequence with the accompanying flowchart) are provided to assist theuser in the field determination of soil texture.

a Adapted from Braumandl and Curran (1992) and Lloyd et al. (1990)

Soil Texture Key

A • 35

• Graininess Test: Rub the soil between your fingers. If sand ispresent, it will feel “grainy”. Determine whether sand makes up more orless than 50% of the sample. Sandy soils often sound gritty when workedin the hand (do you hear the beach?).

• Moist Cast Test: Compress some moist (not wet) soil by clenching itin your hand. If the soil holds together (i.e., forms a “cast”), then test thedurability of the cast by tossing it from hand to hand. The more durableit is (e.g., like plasticine), the more clay is present.

• Stickiness Test: Wet the soil thoroughly and compress it betweenyour thumb and forefinger. Determine degree of stickiness by noting howstrongly the soil adheres to your thumb and forefinger when you releasepressure, and by how much it stretches. Stickiness increases with claycontent.

• Taste Test: Work a small amount of soil between your front teeth. Siltparticles are distinguished as fine “grittiness” (e.g., similar to thatexperienced driving on a dusty road), unlike sand, which is distinguishedas individual grains (i.e., graininess). Clay has absolutely no grittiness.

• Soapiness Test: Slide your thumb and forefinger over wet soil.Degree of soapiness is determined by how soapy/slippery it feels and howmuch resistance to slip there is (i.e., from clay and sand particles).

• Worm Test: Roll some moist soil on your palm with your finger toform the longest, thinnest “worm” possible. The more clay there is in thesoil, the longer, thinner, and more durable the worm will be. Try withwetter or drier soil to ensure that you have the right moisture content(best worm).

Well-decomposed organic matter (humus) imparts silt-like properties tothe soil. Soil feels floury when dry and slippery or spongy when moist,but not sticky and not plastic. However, when subjected to the taste test,it feels non-gritty. It is generally very dark when moist or wet, and stainsthe hands brown or black. Humus-enriched soils often occur on wet sitesin association with a heavy moss cover, and on grasslands. Humus is notused as a determinant of soil texture; an estimate of the silt content ofany humus-enriched mineral soils should be reduced accordingly.

“Organic” soil samples are those that contain more than 30% organicmatter. Soil texture is not determined on organic samples. Most organicsoils and deep organic horizons are found on wet sites, often indepressions or on floodplains, and also in association with dense mosscover (frequently Sphagnum spp.).

Soil Texture Key

A• 36

Soil texture and family particle size triangles

Soil Texture Key

A • 37

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A• 38

Soil Texture Key

A • 39

APPENDIX 12. A soil classification key, to thegreat group levela

This key was devised to aid field staff in classifying soils that may occurin the Prince Rupert Forest Region. Soils may be classified to the orderor great group level of the Canadian System of Soil Classification. Soilhorizons important in classifying soils are defined below.

Designation Definition

Ah Dark-coloured, mineral surface horizon enriched withorganic matter.

Ae Light-coloured, near-surface horizon from which iron,aluminum, organic matter, and clay have been removed.

Ahe Dark grey-streaked surface horizon enriched withorganic matter and depleted of iron and aluminum.

Bf Dark reddish brown to red subsurface horizon, enrichedwith iron and aluminum.

Bhf Reddish brown subsurface horizon, enriched with iron,aluminum, and organic matter.

Bt Brownish subsurface horizon, enriched with clay thathas moved from a horizon above.

Bg Horizon with blue-grey colours and/or mottling (rust-coloured patches), indicative of permanent or periodicanaerobic saturation (gleyed).

Bm Brownish subsurface horizon with only slight additionsof iron, aluminum, or clay.

j Used with suffixes e, f, g, and t to indicate that criteriafor that suffix are weakly expressed “juvenile” and donot meet specified limits (e.g. Bfj, Btgj).

Of, Om, Oh Organic horizons developed mainly from mosses,sedges, rushes, and woody materials under poordrainage conditions. The state of decomposition isdenoted by:

f - fibric, poorly decomposedm - mesic, moderately decomposedh - humic, well decomposed

a After Agriculture Canada Expert Committee on Soil Survey (1987) and Lloyd et al.(1990).

Soil Classification

A• 40

A key to the identification of soil great groups

Soil Classification

A • 41

APPENDIX 13. Humus forms keya

This key assists users in identifying humus forms to the order level,through the use of readily observable forest floor characteristics.

Term Definition

Ah horizon A mineral horizon formed at or near the soil surface and enriched with organic matter.

L horizon The litter layer, consisting of relatively fresh residues of foliage, twigs, wood, and dead moss.

F horizon A horizon in which plant residues are partiallydecomposed; these are discoloured and fragmented, butstill largely recognizable.

H horizon A horizon dominated by well-decomposed organicmaterial; the original structure is no longerrecognizable.

Fungal mycelia A mass of thread-like filaments that constitute the“vegetative” phase of fungal development; many arebrown, black, grey, white, red, or yellow; others aretransparent.

a After Braumandl and Curran (1992) and Lloyd et al. (1990).

Humus Form ID

A• 42

A key to the identification of humus forms

Humus Form ID

A • 43

APPENDIX 14. Common plants of the PrinceRupert Forest Region

Common Names Scientific Names

TREE LAYER

alder, red Alnus rubra (7•88)a

aspen, trembling Populus tremuloides (A•2)birch, Alaska paper Betula neoalaskanabirch, paper Betula papyrifera (5•106)cottonwood, black Populus balsamifera ssp. trichocarpa (A•2)Douglas-fir Pseudotsuga menziesii (3•12)fir, amabilis Abies amabilis (3•12)fir, subalpine Abies lasiocarpa (3•12)hemlock, mountain Tsuga mertensiana (3•12)hemlock, western Tsuga heterophylla (3•12)pine, lodgepole Pinus contorta var. latifolia (A•1)pine, shore Pinus contorta var. contortapine, whitebark Pinus albicaulis (A•1)poplar, balsam Populus balsamifera ssp. balsamifera (A•2)redcedar, western Thuja plicata (A•1)spruce, black Picea mariana (xiv)spruce, Engelmann Picea engelmannii (xiv)spruce, hybrid white Picea engelmannii x glaucaspruce, Roche Picea sitchensis x glaucaspruce, Sitka Picea sitchensis (xiv)spruce, white Picea glauca (xiv)tamarack Larix laricina (A•1)yellow-cedar Chamaecyparis nootkatensis (A•1)yew, western Taxus brevifolia (4•25)

SHRUB LAYER

alder, green Alnus crispa ssp. crispa (7•88)alder, mountain Alnus tenuifolia (7•88)alder, Sitka Alnus crispa ssp. sinuata (7•88)azalea, false Menziesia ferrugineabirch, scrub Betula glandulosa (4•68)blueberries and huckleberries Vaccinium spp.blueberry, Alaskan Vaccinium alaskaense (5•117)blueberry, oval-leaved Vaccinium ovalifolium (5•117)cherry, choke Prunus virginianacinquefoil, marsh Potentilla palustriscinquefoil, shrubby Potentilla fruticosacopperbush Cladothamnus pyroliflorus (5•152)crab apple, Pacific Malus fuscacurrants and gooseberries Ribes spp.currant, northern black Ribes hudsonianum

a The number refers to the page on which a plant illustration occurs.

Species List

A• 44


currant, red swamp Ribes tristecurrant, stink Ribes bracteosumdevil's club Oplopanax horridus (1•4)dogwood, red-osier Cornus stoloniferaelderberry, red Sambucus racemosafalsebox Paxistima myrsinitesgooseberry, black Ribes lacustrehardhack Spiraea douglasii spp. douglasiihazelnut, beaked Corylus cornuta (5•106)highbush-cranberry Viburnum edule (5•80)huckleberry, black Vaccinium membranaceum (5•117)huckleberry, red Vaccinium parvifoliumjuniper, common Juniperus communisjuniper, Rocky Mountain Juniperus scopulorumLabrador tea Ledum groenlandicum (5•13)leatherleaf Chamaedaphne calyculatamaple, Douglas Acer glabrummountain-ashes Sorbus spp.raspberry, red Rubus idaeusrhododendron, white Rhododendron albiflorumrose, Nootka Rosa nutkanarose, prickly Rosa acicularissage, pasture Artemesia frigidasalal Gaultheria shallonsalmonberry Rubus spectabilissaskatoon Amelanchier alnifoliasnowberry, common Symphoricarpos albussoopolallie Shepherdia canadensisspirea, birch-leaved Spiraea betulifoliasweet gale Myrica galethimbleberry Rubus parviflorus (5•80)twinberry, black Lonicera involucratawillows Salix spp.willow, Barclay's Salix barclayi (5•2)willow, Bebb's Salix bebbiana (5•2)willow, bilberry Salix myrtillifoliawillow, bog Salix pedicellariswillow, grey-leaved Salix glauca (5•2)willow, netted Salix reticulata (4• 12)willow, Sitka Salix sitchensiswillow, tea-leaved Salix planifoliawillow, woolly Salix lanata

HERB LAYER

arnica, heart-leaved Arnica cordifolia (4•57)arnica, mountain Arnica latifoliaasphodel, sticky false Tofieldia glutinosaaster, showy Aster conspicuus

Species List

A • 45


baneberry Actaea rubrabeak-sedge Rhynchospora albabearberry, red Arctostaphylos rubrabedstraw, northern Galium borealebedstraw, sweet-scented Galium triflorumbluebells, tall Mertensia paniculata (4•68)blueberry, dwarf Vaccinium caespitosumbluegrass Poa spp.bluegrass, glaucous Poa glaucabluejoint Calamagrostis canadensis (4•90)bog-laurel, western Kalmia microphyllabog-orchid, white Platanthera dilatata (4•16)bog-rosemary Andromeda polifoliabracken Pteridium aquilinumbramble, five-leaved Rubus pedatus (5•127)buckbean Menyanthes trifoliatabulrush, small-flowered Scirpus microcarpusbunchberry Cornus canadensis (5•127)bunchberry, cordilleran Cornus unalaschkensisburnet, great Sanguisorba officinalisburnet, Sitka Sanguisorba canadensis (4•80)buttercup, subalpine Ranunculus eschscholtzii (4•66)cloudberry Rubus chamaemorusclover, alsike Trifolium hybridum (7•82)clubmoss, stiff Lycopodium annotinumclubrush, tufted Trichophorum cespitosumcoltsfoot, palmate Petasites frigida var. palmatuscotton-grass, narrow-leaved Eriophorum angustifoliumcow-parsnip Heracleum lanatumcow-wheat Melampyrum linearecranberry, bog Vaccinium oxycoccuscreeping-snowberry Gaultheria hispidulacrowberry Empetrum nigrumdaisy, subalpine Erigeron peregrinus (4•15)deer-cabbage Fauria crista-gallifairy-slipper Calypso bulbosa (5•188)false Solomon's seal Smilacina racemosafern, beech Phegopteris connectilisfern, deer Blechnum spicant (4•16)fern, lady Athyrium filix-femina (5•20)fern, oak Gymnocarpium dryopteris (4•79)fern, spiny wood Dryopteris expansa (5•20)fern, sword Polystichum munitum (5•20)fescue, Altai Festuca altaicafireweed Epilobium angustifoliumfoamflowers Tiarella spp.foamflower, one-leaved Tiarella unifoliatafoamflower, three-leaved Tiarella trifoliata

Species List

A• 46


geranium, northern Geranium erianthum (4•84)goatsbeard Aruncus dioicusgoldthread, fern-leaved Coptis aspleniifolia (4•88)goldthread, three-leaved Coptis trifoliaground-cedar Lycopodium complanatum (4•83)groundsel, arrow-leaved Senecio triangularis (4•26)hellebore, Indian Veratrum viridehorsetail, common Equisetum arvense (8•6)horsetail, meadow Equisetum pratensehorsetail, swamp Equisetum fluviatile (8•6)horsetail, wood Equisetum sylvaticum (8•6)junegrass Koeleria spp.kinnikinnick Arctostaphylos uva-ursilily-of-the-valley, false Maianthemum dilatatumlingonberry Vaccinium vitisidaealousewort, Labrador Pedicularis labradoricalupine, arctic Lupinus arcticuslupine, Nootka Lupinus nootkatensismarsh-marigold, white Caltha leptosepalameadowrue, western Thalictrum occidentale (4•54)mitrewort, common Mitella nudamountainavens Dryas spp.mountain-avens, yellow Dryas drummondiimountain-heather, Alaskan Cassiope stellerianamountain-heather, clubmoss Cassiope lycopodioidesmountain-heather, pink Phyllodoce empetriformis (4•66)mountain-heather, white Cassiope mertensiana (5•152)mountain-heather, yellow Phyllodoce glanduliflora (5•152)needlegrass Stipa spp.nightshade, enchanter's Circaea alpinaoniongrass, Alaska Melica subulatapaintbrushes Castilleja spp.partridgefoot Luetkea pectinata (4•66)peavine, purple Lathyrus nevadensispinegrass Calamagrostis rubescensprince's pine Chimaphila umbellata (5•127)pyrola, pink Pyrola asarifoliaqueen's cup Clintonia uniflora (4•42)raspberry, trailing Rubus pubescensrattlesnake-plantain Goodyera oblongifoliareedgrass, Pacific Calamagrostis nutkaensisreedgrass, purple Calamagrostis purpurascensricegrass Oryzopsis spp.sage, pasture Artemisia frigidasagewort, mountain Artemisia arcticasarsaparilla, wild Aralia nudicaulissaxifrage, leatherleaf Leptarrhena pyrolifoliascouring-rush, dwarf Equisetum scirpoides

Species List

A • 47


sedges Carex spp.sedge, many-flowered Carex pluriflorasedge, pale Carex lividasedge, Ross' Carex rossiisedge, Sitka Carex sitchensissedge, slough Carex obnuptasedge, soft-leaved Carex dispermasedge, spikenard Carex nardinasedge, water Carex aquatilissedge, yellow-flowered Carex anthoxantheasingle delight Moneses uniflora (4•16)skunk cabbage Lysichiton americanumstarflower, northern Trientalis europaeastrawberry, wild Fragaria virginiana (4•80)sundew, round-leaved Drosera rotundifolia (5•206)sweet-cicely Osmorhiza spp.sweetgrass, alpine Hierochloe alpinatoadflax, bastard Geocaulon lividumtrisetum, nodding Trisetum cernuumtwayblade, heart-leaved Listera cordatatwinflower Linnaea borealis (4•49)twistedstalks Streptopus spp.twistedstalk, clasping Streptopus amplexifoliustwistedstalk, rosy Streptopus roseustwistedstalk, small Streptopus streptopoidesvalerian, Sitka Valeriana sitchensisvetch, American Vicia americanaviolets Viola spp.violet, early blue Viola adunca (5•206)violet, stream Viola glabellawheatgrass, slender Elymus trachycauluswildrye, blue Elymus glaucuswildrye, fuzzy-spiked Leymus innovatuswildrye, hairy Elymus hirsutuswillowherb, broad-leaved Epilobium latifolium (4•58)wintergreen, one-sided Orthilia secundawintergreen, pink Pyrola asarifoliawood-reed, nodding Cinna latifolia (4•90)yarrow Achillea millefolium

MOSS LAYER

dicranum, thin-leaved Dicranum acutifoliumfalse-polytrichum Timmia austriacafeathermoss, red-stemmed Pleurozium schreberi (5•178)lepidozia Lepidozia filamentosalichen, cladonia Cladonia spp.lichen, cladonia Cladonia gonechalichen, cladonia Cladonia gracilislichen, coral Stereocaulon spp.

Species List

A• 48


lichen, dog Peltigera spp.lichen, freckled Peltigera aphthosa (4•86)lichen, green kidney Nephroma arcticumlichen, orange-foot Cladonia ecmocynalichen, red soldier Cladonia bellidiflora (5•178)lichen, reindeer, green Cladina mitislichen, reindeer, grey Cladina rangiferina (5•178)lichen, reindeer spp. Cladina spp.lichen, witch's hair, common Alectoria sarmentosaliverwort, alligator-skin Conocephalum conicumliverwort, cedar-shake Plagiochila porelloidesliverwort, leafy Barbilophozia spp.liverwort, leafy, common Barbilophozia lycopodioides (5•91)liverwort, leafy, golden Herbertus aduncusliverwort, leafy, mountain Barbilophozia floerkeiliverwort, shiny Pellia neesianamoss, bent-leaf Rhytidiadelphus squarrosusmoss, electrified cat's-tail Rhytidiadelphus triquetrusmoss, flat Plagiothecium undulatummoss, glow Aulacomnium palustre (5•178)moss, golden fuzzy fen Tomenthypnum nitensmoss, haircap Polytrichum spp.moss, haircap, juniper Polytrichum juniperinummoss, heron's-bill Dicranum spp.moss, heron's-bill, curly Dicranum fuscescens (5•91)moss, knight's plume Ptilium cristacastrensis (4•76)moss, lanky Rhytidiadelphus loreus (4•76)moss, leafy Mnium, Plagiomnium, Rhizomnium spp.moss, leafy, coastal Plagiomnium insignemoss, leafy, large Rhizomnium glabrescensmoss, leafy Rhizomnium nudummoss, Oregon beaked Kindbergia oreganamoss, palm tree Leucolepis menziesiimoss, pipecleaner Rhytidiopsis robusta (4•76)moss, ragged Brachythecium spp.moss, ragged, woodsy Brachythecium hylotapetummoss, rock Rhacomitrium spp.moss, rock, hoary Rhacomitrium lanuginosummoss, sickle Drepanocladus uncinatusmoss, step Hylocomium splendens (5•178)moss, wiry fern Thuidium abietinumscapania Scapania bolanderisiphula Siphula ceratitessphagnums Sphagnum spp. (5•171)sphagnum, common brown Sphagnum fuscumsphagnum, common green Sphagnum girgensohniisphagnum, common red Sphagnum capillaceumsphagnum, fat Sphagnum papillosum

Species List

A • 49

Appendix 15. Comparison charts for visualestimation of foliage covera

Cover Charts

A• 50

a From Luttmerding et al. (1990).

APPENDIX 16. Mapping procedures fortreatmentunit maps

Outlined here are the steps involved in producing an ecosystem (ortreatment unit) map, at a scale of 1:5000 to 1:20 000, of a relatively small management unit (less than 500 ha). More complex ecosystemmaps of large study areas (watersheds or local resource use planningareas) are generally produced by mapping specialists. Severalconsultants are available throughout the province with experience inthese larger projects. Mitchell et al. (1989) outlines standard methodsand terminology for ecosystem mapping used by the Ministry of Forests,and Courtin et al. (1989) describe an approach to woodlot managementthat incorporates ecological stand mapping. The user should refer tothese publications for more detail on mapping concepts and procedures.

The major steps required to produce an ecological stand map are: 1)preliminary legend production; 2) pre-stratification (typing) of aerialphotographs; 3) systematic field survey; 4) refinement of photo typingand labelling of map polygons; and 5) production of final map.

1 Producing a Preliminary Legend

A legend, in its simplest form, is a listing and explanation of abbreviations(numbers, letters, symbols) used to denote the site units that occur withinthe map area. For the most part, the listing of site series, phases, and seralassociations described for each of the subzones will serve as a preliminarylegend. Other stand or site attributes can also be added depending on therequirements of the survey. For example, symbols for stand age, treespecies composition, or percent slope might supplement the site unitnumbers/letters. Such a legend will enable you to place a preliminarylabel on polygons (map delineations) outlined on the aerial photos.

2 Typing Aerial Photographs

Assuming that aerial photographs of an appropriate scale are available(preferably 1:10 000 colour, but 1:20 000 or 1:15 840 black and white arealso used), the next step is to delineate (using a stereoscope and greasepencil) logical, homogeneous units on the photos that reflect ecological sitecharacteristics. Many features are visible on aerial photos that provideclues to identifying ecological site units. Important features to note arelandform, slope position and degree, slope shape (concave vs convex),aspect, drainage pattern, and canopy characteristics (based on tone andtexture) that will reflect crown closure, species composition, and relativegrowth/productivity. Photo typing is a skill that only improves with muchpractice in combination with ground truthing to calibrate the eyes.

Use the various tools in the guide and your experience to predict what siteunits occur in each of your types (polygons) and put a tentative label (usingsite series numbers or other abbreviations from your legend) on each. Insome cases a polygon may be a complex of two or three units that individ-ually cover too small an area to delineate separately. In this case the

Mapping

A • 51

proportion of each site unit within the map polygon can be indicated bysingle or double slashes (“/ “ for units of roughly equal area or “// “ for thefirst unit dominant over the second) or by actual percentages. Generally,polygons should not be smaller than 1 cm2, which represents .25 ha and 1 ha at 1:5000 and 1:10 000, respectively. Exceptions to this would besmall, easily recognizable features such as wetlands and clearings thatmay require special consideration and also help to orient you on the map.

3 Systematic Field Survey (Ground Truthing)

A properly typed photo facilitates efficient field sampling. Once thetyping is complete, put together a sampling plan, ensuring that there areat least two plots in each type. Complex types may require more plots.Establish plots, sample and describe each of the types as outlined inSection 3.2.1, and identify site units as outlined in Section 3.2.2. Severaltransects should be walked through the area with a compass and a hipchain so as to cross as many types as possible. Take care to locate plotsand transects accurately on the photo. In addition to recording the plotinformation, take notes as you walk and record changes that occur atspecified distances along the transects.

4 Refining and Labelling Map Polygons

The next step is to refine the map polygon boundaries and labels on theaerial photos, based on the results of the field survey. As the transectsand sample plots are completed in the field, modify type lines and labelswhile the information is fresh in your mind. The legend may have to bemodified to accommodate previously undescribed units. Once back in theoffice, finalize the linework, polygon labels, and legend. It may bedesirable to combine similar polygons into “treatment units” if you feelthat the units are not significantly different ecologically to warrantdifferent operational treatments. It is preferable, however, to maintain asmuch detail as possible on the original map and, from this, moregeneralized interpretive maps can be produced for specific applications.

5 Producing the Final Map

Exactly what form the final map takes will depend on its proposed use andthe resources available to produce it. The final product may range from asimple sketch map to a sophisticated colour-themed digital (computer-generated) map. For small settings, where the topography does not varymuch and the map is not very complex, it may be adequate to trace thephoto linework and some of the important planimetric detail (streams,lakes, roads) onto a mylar in order to produce the final map. For largermaps encompassing more than two aerial photos, or where the topographyis variable and steep, the linework will have to be transferred to a basemap using special plotting equipment (e.g., a Kail plotter, zoom transferscope, or epidiascope) that corrects for distortion of scale on the photos.There are several mapping firms throughout the province that specializein Geographic Information Systems (GIS) and the production of digital mapproducts, either directly from aerial photos or from a plotted map. Digital

Mapping

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maps are extremely useful for permanent storage of extensive field databy map polygon. They are ideal for producing interpretive maps and forlong-term monitoring of treatments tied to specific map units.

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APPENDIX 17. Free growing stocking standardsand guidelines for the PRFRa

Pre-Harvest Silviculture Prescriptions

The District Manager must ensure that prescriptions are designed tomeet target free growing stocking standards with the correct tree speciesfor the sites in question. Prescriptions must include sufficient detail todemonstrate this. For example, on sites where pure lodgepole pineplanting is prescribed and no significant ingress is expected tosupplement stocking, the prescription must show that prescribedplanting densities are sufficient to meet targets at free growing.Additionally, where pest risks have been identified, modified initialstocking may be warranted.

Well-spaced Trees Only

The trees used to meet basic silvicultural obligations must be well spacedand of preferred and acceptable species. Both target and minimumstocking standard guidelines consider well-spaced trees only.

The total number of trees and tree species present on an area will, inmost cases, be much higher than that reported as well spaced anddesignated as preferred and acceptable for the purpose of basicsilviculture. These additional trees or tree species may be desirable tomeet other management objectives (e.g., site amelioration or wildlifehabitat), but may not be used to fulfill basic silviculture requirements.

Minimum Stocking for Preferred Species

To satisfy basic silviculture requirements, a minimum number ofpreferred and acceptable well-spaced trees is required at the time of bothregeneration delay and free growing assessments. Of this total, aminimum number of preferred species must also be present at bothassessments before an area can be considered acceptably stocked (Table17A.1).

TABLE 17A.1. Minimum number of well-spaced trees to meetacceptable stocking standards

Stocking StandardsWellspaced stems per hectare

Target at free growing 400 600 800 900 1000 1200(preferred and acceptable)Minimum at regeneration delay 200 400 500 500 500 700(preferred species only)Minimum at free growing 200 400 500 500 500 700(preferred and acceptable)Minimum at free growing 200 400 400 400 400 600(preferred species only)

a Refer to Silviculture Interpretations Working Group (1993) for further explanation(Appendix 17 is an excerpt from that publication).

Stocking Standards

A• 54


In the past, the percentage of acceptable species allowable in determiningwhether an area is satisfactorily restocked has been capped at anarbitrary percentage of the total allowable trees in a plot. The newsystem of requiring a minimum number of well-spaced trees of preferredspecies at both the time of regeneration delay and free growingassessments is more proactive. The new system insists on having thecorrect number of the best species on the site, whereas the old systemwas more concerned with restricting the numbers of less desirablespecies on the site.

Minimum stocking standard guidelines represent densities below whichyield will be significantly lowered, given anticipated final crop densitieswithin planned rotations.

A uniform target and minimum stocking standard was established for allconiferous species in order to reflect the current precision of silviculturesurveys and operational field survey constraints.

Minimum and target stocking standards assume a level of normal oraverage random mortality beyond free growing. Where local experienceor conditions indicate higher levels of random mortality, stocking levelsshould be increased.

Regeneration Delay

For the CWH, CDF, ICH, SBS, SBPS, BWBS, IDF, MS, BG, and PPzones, regeneration must be established on site at least 5 years before afree growing assessment (i.e., early free growing date equals actualregeneration delay achieved plus 5 years). For the ESSF and MH zones,this establishment period is 8 years. If the regeneration is achievedearlier than specified in the PHSP, the early free growing date may beadvanced by the same amount, resulting in a possible earlier fulfilmentof basic silvicultural obligations.

In these guidelines, the short regeneration delay periods indicate thatartificial regeneration is the preferred method of reforestation. The longregeneration delay periods indicate that either planting or naturalregeneration may be acceptable methods. Where both natural andartificial regeneration are acceptable options in the PHSP, theseguidelines recommend that the long regeneration time frames be used forregeneration delay and free growing, regardless of the regenerationmethod selected. By stating that either option is acceptable, we aretherefore willing to accept the longer time frames, which allowsreasonable flexibility in planning and does not penalize those who opt toplant. Timing can always be advanced if goals are achieved ahead ofschedule. To achieve this, an amendment must be made to the PHSP.

Stocking Standards

A • 55


Free Growing Seedling Definition

The free growing seedling definition was standardized for the CWH,CDF, ICH, SBPS, BWBS, SBS, and Vancouver Forest Region IDFww. Itspecifies a crop tree/brush ratio within the 1-m radius cylinder such thatthe crop tree must be 150% of the height of the competing vegetation. Forthe ESSF, IDF, MH, MS, PP, and BG zones, the ratio must be 125%.

A tree meets the free growing definition when:

• it is healthy, undamaged, and well spaced;

• it meets the minimum age criteria; and

• it meets the size standards (relative to competing vegetationwithin the effective growing space).

The rationale for the extended early free growing date and lower croptree/brush ratio for the ESSF and MH is based on generally slowerconifer growth rates and single-layer brush communities. By comparison,other zones have more rapid growth rates for both crop trees andcompeting vegetation with a more complex, multi-layer brushcommunity, hence the more secure crop tree/brush ratio of 150%.

If a 150% ratio is achieved in the ESSF or MH zones 5 years afterregeneration delay, it is recommended that the District Manager declarethe area free growing

In general, the District Manager has the flexibility to declare an area tobe free growing before the specified early free growing date if all otherfree growing objectives/criteria have been met. Such incentives must beavailable to encourage the practice of quality silviculture in return forprompt relief of obligations.

A free growing survey will not be completed immediately following abrushing treatment. The vegetation must be given time to “recover”before a realistic assessment of free growing can be made. For the ICH,IDF, MS, PP, BG, SBPS, CWH, CDF, MH, and ESSF zones, this periodwill be a minimum of two complete growing seasons. For the SBS andBWBS zones, this period will be a minimum of three complete growingseasons if brush control was done using herbicides, and three completegrowing seasons if the site was manually or otherwise treated. Thedifferent periods are based on perceived differences in conifer growthrates and brush re-invasion rates in these zones.

Stocking Standards

A• 56

AP

PE

ND

IX 1

7.(C

onti

nu

ed)

Tab

le 1

7A.2

.F

ree

grow

ing

stoc

kin

g st

anda

rds

guid

elin

es f

or t

he

Pri

nce

Ru

pert

For

est

Reg

ion

BW

BS

Zon

e Sit

e se

ries

Sto

ckin

g s

tan

da

rds

Reg

ener

ati

on

Ass

essm

ent

% t

ree

ov

er(w

ell-

spa

ced

/ha

)d

ela

yE

arl

iest

La

test

bru

sh

BW

BS

dk

1B

WB

Sd

k2

Ta

rget

Min

imu

m(y

ears

)(y

ears

)(y

ears

)

01/0

3/04

/05

01/0

3/05

1200

700

712

1515

006

/07

0806

1000

500

49

1515

002

0210

0050

07

1215

150

0410

0050

04

915

150

09/1

0/11

07/0

840

020

04

915

150

31/3

2/81

31/3

2/81

00

00

00

Stocking Standards

A • 57

AP

PE

ND

IX 1

7.(C

onti

nu

ed)

Tab

le 1

7A.2

.(C

onti

nu

ed)

CW

H Z

one

Sit

e se

ries

Sto

ckin

g s

tan

da

rds

Reg

ener

ati

on

Ass

essm

ent

% t

ree

ov

er(w

ell-

spa

ced

/ha

)d

ela

yE

arl

iest

La

test

bru

sh

CW

Hv

h2

CW

Hv

m1

CW

Hv

m2

Ta

rget

Min

imu

m(y

ears

)(y

ears

)(y

ears

)

01/0

401

/06

01/0

690

050

06

1114

150

05/0

6/07

/08/

09/1

5/17

04/0

5/07

/08/

09/1

004

/05/

07/0

890

050

03

811

150

0303

0380

040

06

1114

150

13/1

112

/14

09/1

180

040

03

811

150

02/1

2/14

/16/

18/1

902

/13

02/1

040

020

03

811

150

10/3

1/32

/33

11/3

1/32

/51

31/3

2/51

00

00

00

Sit

e se

ries

Sto

ckin

g s

tan

da

rds

Reg

ener

ati

on

Ass

essm

ent

% t

ree

ov

er(w

ell-

spa

ced

/ha

)d

ela

yE

arl

iest

La

test

bru

sh

CW

Hw

mC

WH

ws1

CW

Hw

s2T

arg

etM

inim

um

(yea

rs)

(yea

rs)

(yea

rs)

01/0

2/08

01/0

3/05

01/0

3/05

900

500

611

1415

003

/04/

05/0

604

/06/

07/0

804

/06/

07/0

890

050

03

811

150

0911

1180

040

03

811

150

0202

600

400

611

1415

010

1010

400

200

38

1115

007

/31/

32/5

109

/31/

3209

/31/

32/5

10

00

00

0

Stocking Standards

A• 58

AP

PE

ND

IX 1

7.(C

onti

nu

ed)

Tab

le 1

7A.2

.(C

onti

nu

ed)

ES

SF

Zon

e

Sit

e se

ries

Sto

ckin

g s

tan

da

rds

Reg

ener

ati

on

Ass

essm

ent

% t

ree

ov

er(w

ell-

spa

ced

/ha

)d

ela

yE

arl

iest

La

test

bru

sh

ES

SF

mc

ES

SF

mk

ES

SF

wv

Ta

rget

Min

imu

m(y

ears

)(y

ears

)(y

ears

)

01/0

401

/03

01/0

3/04

1200

700

715

2012

505

/06/

0704

/05

05/0

612

0070

04

1220

125

02/0

302

0210

0050

07

1520

125

08/0

9/10

06/0

707

/08/

0910

0050

04

1220

125

31/5

131

/51

31/5

10

00

00

0

ICH

Zon

e

Sit

e se

ries

Sto

ckin

g s

tan

da

rds

Reg

ener

ati

on

Ass

essm

ent

% t

ree

ov

er(w

ell-

spa

ced

/ha

)d

ela

yE

arl

iest

La

test

bru

sh

ICH

mc1

ICH

mcl

aIC

Hm

c2IC

Hv

cIC

Hw

cT

arg

etM

inim

um

(yea

rs)

(yea

rs)

(yea

rs)

01/0

3/04

/05

01/0

2/03

01/0

3/04

/05/

06/

01/0

2/03

/04/

0501

/03/

04/0

5/06

1200

700

49

1515

051

/52/

53/5

402

0202

1000

500

712

1515

006

0706

07/0

8/51

1000

500

49

1515

051

1000

500

38

1115

052

5240

020

03

811

150

0840

020

04

915

150

3131

/32

3131

/32

00

00

00

Stocking Standards

A • 59

Tab

le 1

7A.2

.(C

onti

nu

ed)

MH

Zon

e

Sit

e se

ries

Sto

ckin

g s

tan

da

rds

Reg

ener

ati

on

Ass

essm

ent

% t

ree

ov

er(w

ell-

spa

ced

/ha

)d

ela

yE

arl

iest

La

test

bru

sh

MH

mm

1M

Hm

m2

MH

wh

Ta

rget

Min

imu

m(y

ears

)(y

ears

)(y

ears

)

01/0

401

/04

01/0

3/04

900

500

715

2012

503

/05/

0703

/05/

0705

/07

900

500

412

2012

506

0606

800

400

715

2012

502

/09

02/0

909

800

400

412

2012

508

0802

/08

400

200

412

2012

531

/51

31 /5

131

00

00

00

SB

S Z

one

Sit

e se

ries

Sto

ckin

g s

tan

da

rds

Reg

ener

ati

on

Ass

essm

ent

% t

ree

ov

er(w

ell-

spa

ced

/ha

)d

ela

yE

arl

iest

La

test

bru

sh

SB

PS

mc

SB

Sd

kS

BS

mc2

Ta

rget

Min

imu

m(y

ears

)(y

ears

)(y

ears

)

01/0

301

/03/

04/0

501

/03/

0412

0070

07

1215

150

06/0

805

/06/

08/0

912

0070

04

915

150

0202

0210

0050

07

1215

150

04/0

5/06

0707

/10/

1110

0050

04

915

150

0709

/10

1240

020

04

915

150

31 /3

231

/32/

81/8

231

00

00

00

Stocking Standards

A• 60

APPENDIX 18. Glossary of common and scientificnames of common forest pests

Common name Scientific name Pest code

Diseases

Annosus Root Disease Heterobasidion annosum (=Fomes annosus) DRNAtropellis Canker Atropellis piniphila DSAComandra Blister Rust Cronartium comandrae DSCFir Broom Rust Melampsorella caryophyllacearum DAFHemlock Dwarf Mistletoe Arceuthobium tsugense DMHLodgepole Pine Dwarf Arceuthobium americanum DMP

MistletoePhellinus Root Disease (cedar Phellinus weirii (=Poria weirii) DRC

strain)Rhizina Root Disease Rhizina undulata DRRShepherd's Crook Disease Venturia macularis DLLSpruce Broom Rust Chrysomyxa arctostaphyli DAFStalactiform Blister Rust Cronartium coleosporioides DSSTomentosus Root Disease Inonotus tomentosus (=Polyporus tomentosus) DRTWestern Gall Rust Endocronartium harknessii DSG

Insects

Black Army Cutworm Actebia fennica IDALodgepole Pine Terminal Pissodes terminalis IWP

WeevilPoplar and Willow Borer Cryptorhynchus lapathi IWMountain Pine Beetle Dendroctonus ponderosae IBMSpruce Bark Beetle Dendroctonus rufipennis IBSSpruce Leader Weevil Pissodes strobi IWSTwo-Year-Cycle Budworm Choristoneura biennis IDBWarren's Root Collar Weevil Hylobius warreni IWWWestern Balsam Bark Beetle Dryocetes confusus IBBWestern Blackheaded Budworm Acleris gloverana IDHWestern Forest Tent Caterpillar Malacosoma californicum IDF

Mammals

Deer Odocoileus spp. ADPorcupine Erethizon dorsatum APSnowshoe Hare Lepus americanus AHTree Squirrel Tamiasciurus spp. ASVole Microtus spp. AV

Common Forest Pests

A • 61

Request for Revisions

This document represents the first region-wide guide for ecosystemidentification and interpretation in the Prince Rupert Forest Region.Revisions and additions will be made to this guide following developmentof other site interpretations and further sampling. To ensure that you arenotified about future revisions and field guide inserts please print yourname and address below and mail to:

Regional Research Ecologist B.C. Ministry of Forests Bag 5000 Smithers, B.C. V0J 2N0

Please notify me of changes and additions or revisions made to: “A fieldguide to site identification and interpretation for the Prince RupertForest Region”.

Name: ____________________________________________

Address: ____________________________________________

____________________________________________

____________________________________________

Tel./E-mail: ____________________________________________

Comments: Your comments on this publication are required to improvethe presentation of further BEC information. Please write yourcomments, suggestions, and criticisms below and overleaf, and mail tothe above address.