Woody Biomass onWoody Biomass onWisconsin ForestlandWisconsin Forestland

Vern EversonWisconsin DNR- Div. of Forestry

Forest Inventories

• First - 1936

• Second - 1956• Third - 1968

•• Fourth Fourth -- 19831983•• Fifth Fifth -- 19961996•• Sixth Sixth -- 20002000--0404

Timberland Acres, 1936Timberland Acres, 1936--19961996

-

2,000,000

4,000,000

6,000,000

8,000,000

10,000,000

12,000,000

14,000,000

16,000,000

18,000,000

1936 1956 1968 1983 1996

Year

Tim

berla

nd A

cres

All timberland ownership, 1996All timberland ownership, 1996National Forest

9%

Other Federal1%

State5%

County and Municipal15%

Tribal2%

Forest Industry7%

Private landowner61%

-

1,000,000

2,000,000

3,000,000

4,000,000

5,000,000

6,000,000

PineSpru

ce-Fir

Swamp co

nifers

Maple-

Bassw

oodAsp

en-B

irch

Oak-H

ickory

Soft map

le-Ash

Nonstock

ed

Acr

es

1936 1956 1968 1983 1996

Timberland by forest type group, 1936Timberland by forest type group, 1936--9696

Timberland by forest type group, 1996Timberland by forest type group, 1996Pine8% Spruce-Fir

2%

Swamp conifers6%

Maple-Basswood34%

Aspen-Birch22%

Oak-Hickory18%

Soft maple-Ash10%

All Timberland Acreage by Stand Age Class

-

1,000.0

2,000.0

3,000.0

4,000.0

5,000.0

6,000.0

1-20 21-40 41-60 61-80 81-100 101-120 121+Stand Age Class (Years)

Thou

sand

Acr

es

1996 1983 1968

USDA Forest Service Survey Units

Southwest Unit

Northwest Unit Northeast Unit

Southeast Unit

Central Unit

Timberland by Forest Survey Unit, 1983-96

- 1,000,000 2,000,000 3,000,000 4,000,000 5,000,000 6,000,000

Northeast

Northwest

Central

Southwest

Southeast

ACRES

1983 1996

Total growing stock volume, 1936-1996

-

2,000

4,000

6,000

8,000

10,000

12,000

14,000

16,000

18,000

20,000

1936 1956 1968 1983 1996

Mill

ion

cubi

c fe

et

Hardwoods Conifers

Net Volume of Growing Stock Volume on Timberland by Diameter Class Group

-2,0004,0006,0008,000

10,00012,00014,00016,00018,00020,000

1956 1968 1983 1996

Year

Mill

ion

Cub

ic F

eet

Large sawtimberSmall sawtimberPoletimber

Growing Stock Volume on

Total Growing Stock Volume on Timberland by Forest Survey Unit

- 2,000 4,000 6,000 8,000

Northeast

Northwest

Central

Southwest

Southeast

Fore

st S

urve

y U

nit

Million Cubic Feet1983 1996

Current Annual Growth and Removals of Growing Stock on Timberland

-100200300400500600

1956 1968 1983 1996

Year

Mill

ion

Cub

ic F

eet

GrowthRemovals

All Live Tree Biomass by Component, 1996All Live Tree Biomass by Component, 1996

- 100 200 300 400 500 600

1 to 5-inch trees

Stumps

Boles

Tops & Limbs

Stumps

Boles

Tops & Limbs

Gro

win

g St

ock

Cul

l

Million Green Tons

All Live Tree Biomass by Ownership, 1996All Live Tree Biomass by Ownership, 1996National Forest

10%

Other Federal1%

State5%

County and Municipal13%

Indian lands3%

Forest Industry7%

Private landowner61%

All Live Tree Biomass by Major Species GroupAll Live Tree Biomass by Major Species Group

-

200

400

600

800

1,000

1,200

Mill

ion

Gre

en T

ons

Noncommercial 12 9 Hardwoods 779 866 Conifers 170 183

1983 1996

All Live Tree Biomass by Forest Survey UnitAll Live Tree Biomass by Forest Survey Unit

- 50 100 150 200 250 300 350 400

Northeast

Northwest

Central

Southwest

Southeast

Fore

st S

urve

y U

nit

Million Green Tons1983 1996

All Live Tree Biomass by Forest Type Group All Live Tree Biomass by Forest Type Group and Tree Class, 1996and Tree Class, 1996

-

50

100

150

200

250

300

350

400

450

500

Pine Spruce-fir Oak-hickory Soft Maple-Ash

Maple-basswood

Aspen-birch

Forest Type Group

Mill

ion

Gre

en T

ons

Growing stock Rough cull Rotten cull

Merchantable and All Live Tree Biomass by Forest Merchantable and All Live Tree Biomass by Forest Type Group, 1996Type Group, 1996

-

50

100

150

200

250

300

350

400

450

500

Pine Spruce-fir Oak-hickory Soft Maple-Ash

Maple-basswood

Aspen-birch

Forest Type Group

Mill

ion

Gre

en T

ons

Merchantible All Live

All Live Tree Biomass per Acre by Forest All Live Tree Biomass per Acre by Forest Type Group, 1996Type Group, 1996

58

49

43

64

44

73

46

-

10

20

30

40

50

60

70

80

All ForestTypes

Pine Spruce-Fir Oak-Hickory

Soft maple-Ash

Maple-Basswood

Aspen-Birch

Forest Type Group

Gre

en T

ons/

Acr

e

Woody Shrubs and Seedlings Biomass per Woody Shrubs and Seedlings Biomass per Acre by Forest Type Group, 1996Acre by Forest Type Group, 1996

1.2

2.6

1.6

4.7

2.1

4.1

2.7

-

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

Pine Spruce-fir Oak-hickory

Soft Maple-Ash

Maple-basswood

Aspen-birch

All ForestTypes

Forest Type Group

Gre

en T

ons/

Acr

e

Annual Wood Residue Production, 1990Annual Wood Residue Production, 1990

-

200

400

600

800

1,000

1,200

Northeast Northwest Central Southwest Southeast

Forest Survey Unit

Thou

sand

Ton

s

Wood-using mills Non-wood using mills

Summary• Private landowners own majority (61%)

of woody biomass.

• Over one billion tons of tree biomass.

• Live tree biomass greatest on Oak-hickory and Maple-basswood forest types

• Shrubs and Seedlings constitute less than 5% of total woody biomass.