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Iowa's Forest Resources, 2008
From Forest Service, US Department of
Agriculture Northern Research Station
This publication provides an overview of
forest resource attributes for Iowa based on an annual inventory (2004-2008)
conducted by the Forest Inventory and Analysis (FIA) program of the U.S. Forest
Service, Northern Research Station.
These estimates, along with web posted core tables, are updated annually.
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Table 1. - Annual estimates, sampling errors, and
change, Iowa, 2004-2008 |
| |
Estimate |
Sampling error (%) |
Change
since 1999-2003 (%) |
|
Forest Land Estimates |
| Area (1,000 acres) |
3,033 |
2.5 |
13.8 |
|
Number of live trees 1-inch diameter or
larger (1,000,000 trees) |
1,159 |
4.2 |
11.8 |
| Biomass of live trees
1-inch diameter or larger (1,000 tons) |
114,682 |
3.7 |
11.8 |
| Net volume of live trees
(1,000,000 ft3) |
4,256 |
4.3 |
11.4 |
| Annual net growth of live
trees (1,000 ft3/year) |
143,562 |
8.5 |
-- |
| Annual mortality of live
trees (1,000 ft3/year) |
61,047 |
8.6 |
-- |
| Annual harvest removals of
live trees (1,000 ft3/year) |
26,889 |
23.0 |
-- |
| Annual other removals of
live trees (1,000 ft3/year) |
21,780 |
25.3 |
-- |
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Timberland Estimates |
| Area (1,000 acres) |
2,970 |
2.6 |
15.2 |
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Number of live trees 1-inch diameter or
larger (1,000,000 trees) |
1,134 |
4.2 |
12.4 |
| Biomass of live trees
1-inch diameter or larger (1,000 tons) |
111,251 |
3.7 |
11 |
| Net volume of live trees
(1,000,000 ft3) |
4,115 |
4.3 |
10.1 |
| Net volume of
growing-stock trees (1,000,000 ft3) |
3,027 |
5.1 |
4.6 |
| Annual net growth of
growng-stock trees (1,000 ft3/year) |
102,528 |
8.4 |
-12.7 |
| Annual mortality of
growing-stock trees (1,000 ft3/year) |
36,288 |
11.4 |
48.1 |
| Annual harvest removals of
growing-stock trees (1,000 ft3/year) |
20,449 |
26.0 |
7.2 |
| Annual other removals of
growing-stock trees (1,000 ft3/year) |
25,234 |
45.5 |
292.6 |
| Note: Sampling
errors and error bars shown in the tables and figures in this report
represent 68% confidence intervals for the estimated values. Volumes
are for 5-inch and larger diameter trees. |
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Table 2. - Top 10 tree species by
statewide volume estimates, Iowa, 2004-2008 |
| Rank |
Species |
Volume
of live trees
on forest land (1,000,000 ft3) |
Sampling
error
(%) |
Change
since
1999-2003
(%) |
Volume
of sawtimber trees on timberland (1,000,000
bd ft) |
Sampling
error
(%) |
Change
since
1999-2003
(%) |
| 1 |
Silver Maple |
485.0 |
18.4 |
17.3 |
1,127.3 |
21.0 |
3.2 |
| 2 |
Bur Oak |
476.4 |
11.4 |
19.2 |
1,081.3 |
14.5 |
13.8 |
| 3 |
Cottonwood |
367.1 |
28.1 |
8.4 |
1,521.9 |
28.4 |
3.0 |
| 4 |
White Oak |
350.2 |
14.1 |
-5.2 |
1,172.9 |
15.6 |
-2.2 |
| 5 |
Black Walnut |
282.6 |
12.0 |
27.1 |
966.2 |
14.3 |
28.7 |
| 6 |
Northern Red Oak |
231.3 |
14.8 |
-14.9 |
868.3 |
16.7 |
-16.5 |
| 7 |
American Elm |
222.3 |
8.1 |
-3.8 |
323.5 |
16.0 |
-18.5 |
| 8 |
American basswood |
199.4 |
14.5 |
20.7 |
681.1 |
17.0 |
23.0 |
| 9 |
Hackberry |
194.5 |
12.6 |
17.2 |
491.4 |
16.6 |
25.8 |
| 10 |
Shagbark Hickory |
166.5 |
11.7 |
2.6 |
444.0 |
15.4 |
10.8 |
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Other softwood species |
47.5 |
16.5 |
15.9 |
64.5 |
27.1 |
-36.3 |
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Other hardwood species |
1,233.3 |
5.0 |
18.7 |
2,417.0 |
7.9 |
12.6 |
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All species |
4,256.1 |
4.3 |
11.4 |
11,159.4 |
5.9 |
6.3 |
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