NREM 301Forest Ecology & Soils

Day 15 – October 7, 2008

1. Review Quiz2. Tree & Stand Growth3. Lab today – Tree & Stand Growth (Reactor Woods)4. Soper’s Mill Cross-section Due Thursday4. Take Home Test next Tuesday

Provide definitions for the following terms:a) Horizontal stratification – variation in clipsrot along a

horizontal transectb) Ecosystem forming factors – Clipsrot – spell out each

one and include s.c) Conservation easement – constraints placed on land to

protect against future development – stay with the deed, not owner.

d) Elluviation – loss of clay and some minerals by leaching – process involved in E horizon development

e) Soil biosequence – changes in soils due to changes in vegetation or Cliprot – O. Other factors like r (topography) held constant.

f) Gravitational water – water held in macropores in the soil for a short period after a rain event – water that drains in response to gravity because of the large size of the macropores it is in – usually soils drained after rain in 24-48 hours – moves to fast to be of use to plants

Vertical & Horizontal Stratification

Vertical Stratification – various canopies in forest

Horizontal Stratificationlake, floating plant mat, forest

Gravitational Water – pulled down through macropores by gravity – not of much use to plants – not around long.

Field Capacity – water held against gravity by forces of tension (cohesion/adhesion) – readily accessible to plants

Available Water – roots can produce enough tension to pull water away from soil particles – water enters plant

Wilting Point – tension at which water is held so tightly that plants cannot pull it out of soil

Kinds of Soil Water

Page 17

Individual - 2 This stream is:a) Autochthonous or Allochthonous

inputs of carbonb) Heterotrophic or Autotrophicc) Why – Give examples to support

your answer.d) Is embeddeness a problem – why

or why not? (Not in picture)

River Continuum ConceptHeterotrophic/Allochthonous

Autotrophic/Autochthonous

Individual 3For each structural element below identifya soil horizon where it is most likely to be found

AB

C D

B horizons

E Horizon A Horizon

Diagram a stream showing the following parts:

2 pools2 rifflesAt least 1 point barAt least 1 runThe Thalweg through the whole diagram

Group 1

Meandered Reach

Straight ReachRun

Roots on this big tree are more exposed on the uphill or downhill side? Why?

What Slope Position are They On?What positions are above & below this one?

What major species of trees would you expect to see on this N-facing slope?On a S-facing slope?

Parent Material on this summit is?How does soil depth here compare to that on a back slope & footslope?

Group  2Soper’sMill Sitea

b

c d

More exposed downhill side because of sediment deposition on the uphill side and erosion on the downhill side.

S-facing: red oak, white oak, hickory, ironwoodN-facing: sugar or black maple, basswood, ash, hackberryNeed 2 on each slope.

Backslope, shoulder above, foot below

Glacial tillSoil deeper on summit than backslope – summit deeper than or equal too footslope – with more developed horizons

Identify the Soils You Would Expect At Each Number By Name

12

5 6

78

9 10 11

1243

ConcentricDepression

Elongated Depression

Group 3Central IowaDoolittle, Reactor WoodsSkunk River Greenbelt

Har

ps

Oko

boji

Stor

den

Web

ster

/Can

iste

ao

Cla

rion

or N

icol

let

Hay

den

Stor

den

Terr

ill Coland Spillville

Hanlon

Soil Landscape Model for Central Iowa

Coland-Spillville-ZookAssociation

Hayden-Lester-StordenAssociation

Clarion-Webster-NicolletAssociation

Upland Soils – Clarion-Webster-Nicollet Association

Note: Parent materials – glacial till or local alluviumUpland depressional soil sequence from center out –

Okoboji 6, Harps 95, Canisteo 507Webster 107 - depressional, non-circular soil

Best drained soils – Clarion 138 & Storden 62 but Storden is erodedNicollet – somewhat poorly drained

Upland Hillslope Soils – Hayden-Lester-Storden Association

Parent Materials – Glacial Till, Colluvium, Alluvium, Bedrock

Lester – summit, shoulder, well-drained, loam, formed under savanna vegetation

Hayden – shoulder, upper back slope, well-drained loam, formed under forest

Storden – back slope, shallow loam, well-drained, formed under forestTerril – foot slope, well-drained loam, formed under forest

Coland – foot slope, poorly drainedClay loam along small creeks

Flood Plain Soils Along the Skunk River

Coland-Spillville-Zook Soil Association Flood Plain-Toe Slope

Parent Material –Alluvium

Spillville – blackLoam, moderatelyWell drained

Coland – blackClay loam, poorlydrained

Zook – blackSilty clay loam,Poorly drained

Hanlon – natural levee, sandy loamWadena & Biscay minor soils

What Plant Communities Marched Through Iowa Since The Retreat of the Last Glacier? Why?

Why are Savanna Often Found on Shoulders, Deciduous Forests on Back, Foot & Toe Slopes, & Conifers Nowhere?

Team Activity

2,500,000 to 500,000 years300,000 – 130,000 years30,000 – 10,500 years Glacial Changes Over Time – EcosystemsChanged Also

Use Figure 3.5 in the text to describe the major plant communities that have existed in Iowa over the past 18,000 years

Page 49

X X

XX

10,500 – 30,000 ybp500,000 – 2,500,000 ybp 130,000 – 300,000 ybp

What sequence of plant communities preceded the Soper’s Mill Deciduous forest that we visited since the most recent glaciation?

TundraBoreal ForestMixed Conifer/DeciduousEastern DeciduousSavannaTall Grass Prairie/Savanna? Climate Change2030 – temp + 5 F precip + 1”2095 – temp + 12 F precip + 20”

Des Moines Register 10-05-08

1

2

3456

78

11

12

7 9

10

MatchBiome Name

With MapNumber

Coastal Plain Conifers

Tall Grass Prairie

Central Valley

Mountain conifers &Semi-arid shrubland

Tundra

Short Grass Prairie

Great Basin Desert

Intermountain Grassland

Mixed Prairie

Boreal

Pacific Coast Conifer Forest

Eastern Deciduous

Team Activity

Biomes:

1 Tundra

2 Boreal

3 Eastern Deciduous

4 Tall Grass Prairie

5 Mixed Prairie

6 Short Grass Prairie

7 Mountain conifers &Semi-arid shrubland

8 Great Basin Desert

9 Intermountain Grassland

10 Central Valley

11 Pacific Coast Conifer Forest

12 Coastal Plain Conifers

1

2

3456

78

11

12

7 9

10

Tree & Stand Growth

Please look at Reactor Woods Lab Handout

Each team has been assigned 1 or 2 topics to describe

Take a large sheet of paper and markers and prepare to present your information to a “Master Woodland Managers” workshop.

Workshops are offered to private citizens who want to learn more about trees and managing forests. Give 30 hrs of volunteer labor after finishing. Offered by ISU Extension.

Make diagrams large enough for all to see – you will present the information to the class (workshop attendees).

This is an Interpretation Exercise

Group 1 - #’s 1 & 2 Group 2- # 3 & 4

Group 3 - # 5 Group 4- # 6

Group 5 - # 7 Group 6 - # 8

Group 7 - # 9 Group 8 – # 10

Group 9 - # 11 Group 10 - # 12 & 13