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PROPOSED
MEASURES: EXTENT, TYPE & OWNERSHIP
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Total area of
forest, for the United States and its major regions, as an overall
measure of the quantity of the Nation's forests. (Figs. 1
& 2)
Area of 21 common
forest types for the East and West, because different forest types
have different value as habitat and for commercial harvest. (Figs.
3 & 4)
Ownership of
U.S. forests, because different types of owners often manage forests
quite differently. (Fig. 5)
Forests (defined
by the Forest Service as lands with at least 10 percent tree cover)
currently cover 737 million acres, or 33 percent of the United States.
At the time of European settlement, forests covered about 1 billion
acres; most of the clearing has occurred in the eastern states.
Total forest area
in the Western states and Alaska remained stable from 1977 to 1992.
In the West, three common forest types: fir-spruce, Douglas fir, and
hardwoods increased in area, while lodgepole pine and chaparral, also
common, declined.
Eastern forests
as a whole declined slightly in area; northern forests expanded, and
southern forests contracted. The two most widespread forest types in
the eastern United States (oak-hickory and maple-beech-birch) both increased
in area from 1977 to 1992 Loblolly-shortleaf pine, which accounts for
over half of eastern conifer forests, remained stable in area.
Forty-two percent
of U.S. forests are publicly owned and 58 percent are privately owned.
Private ownership is dominant in the East and federal ownership in the
West.
| Forest
area by region, 1630-1992 (2) Technical
Note |
 |
| Source:
USDA Forest Service, Forest Inventory & Monitoring |
| Western
forest types, 1977 & 1992* (3) Technical
Note |
 |
*
This graph includes 129 million acres of forest in Alaska. Alaskan
forest cover is predominantly of fir-spruce (about 95 million acres),
Hemlock-Sitka spruce (14 million acres) and western hardwood (20
million acres). It is estimated that this distribution has changed
little since 1977 due to low rates of human disturbance. |
| Source:
USDA Forest Service, Forest Inventory & Monitoring |
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Eastern
forest types, 1977 & 1992 (4)
Technical
Note |
Forest
land ownership, 1992 (5)
Technical
Note |
 |
 |
| Source:
USDA Forest Service, Forest Inventory & Monitoring |
Source:
USDA Forest Service, Forest Inventory & Monitoring |
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STATUS
OF DATA & OTHER NOTES
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All data
on this page are from a continuing monitoring program, the Forest
Service's Forest Inventory and Analysis Program.
Satellite
measurements (map) and ground-based surveys (graphs) often use
slightly different definitions and criteria for "forest." These
have not been reconciled for this report.
This page
presents information on major forest types, using a classification
system employed by the Forest Service. This classification does
not distinguish between naturally generated forest and planted
forest/tree farms/plantations. Consideration will be given to
incorporating this distinction into future reports. In addition,
this report includes information on other characteristics of forest,
such as age/size class and different vegetation community types.
See Forests, Biological
Community Condition.
Please see the
Technical
Notes for additional information. |
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