Hardwood Growth and Yield Model(Growth & Yield 1.1.0)

Project Report 2005

Tim McGrathRob O’KeefeBrad MacPhee

Hardwood GNY Model

Computer model Predicts yields of even-aged single species

hardwood stands Compare results of managed vs unmanaged Help prescribe treatment timing and

intensity

CFRU Deliverables

Re-measurement of Hardwood PSPsCompleted 2004

Refinement of Hardwood GNY ModelCompleted 2005

User Manual/Model descriptionDraft 2005

Hardwood GNY 1.1.0

Items to Cover:Model DevelopmentDemonstrationApplication

Development

Objectives:Refit existing growth function to a PSP database

that has nearly doubled in size since 1997

Investigate updating existing or developing new functions to better capture species group and site class variation

Development HighlightsThe Data

Key Classifications:Treatment, Species Group, Site Index

Dev

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The

Mod

el 2005 Hardwood Growth and Yield ModelFlow diagram of primary functions:

Development HighlightsExample: Manage Stand Diameter Function (F18)

Species Group Incorporation

TD as ƒ(SIB,TBA,Species Group)

Model:

251410 32 DVDVeSIBTD TBASIB

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luat

ion

Res

ults

2005 Hardwood Growth and Yield Model 1997 and 2005 Model Performance Comparison:

TolerantGroup

IntolerantGroup

AspenGroup

Demonstration

Single Run Mode Input

The 7 steps, Help Output

Definitions, Graphing

Batch Mode Input

Text files Output

Text, HTML

Hardwood GNY 1.1.0Input

Hardwood GNY 1.1.0Output

Hardwood GNY 1.1.0Output

Application Samples

Pre-commercial Thinning spacing Commercial Thinning timing Commercial Thinning vs no treatment

Pre-Commercial Spacing?

8’x8’6’x6’

6” Dbh

4” Dbh

Commercial Thinning Timing?(Pre-commercial Thin@ 20 to 8’)

Thin@35 Thin@50

Commercial Thinning or Not?

Thin@60&85

Growth & Yield 1.1.0

Download modelhttp://www.gov.ns.ca/natr/forestry/gny2004/gro

wthandyield.htm

CommentsTim McGrath NSDNR (902) 893-5683 tpmcgrat@gov.ns.ca