2002
3
2
Western
white
pine
0
Redwood
1
Larch
Million acres
Western
broadleaves
Pinyonjuniper
1977
4
Aspenbirch
Maplebeech-birch
Elm-ashcottonwood
Oakhickory
SOUTH
2002
Oakhickory
NORTH
1990
1960
1930
1900
1870
1840
1810
1780
1720
1750
1690
1660
1630
1600
0
Longleafslash pine
50
1977
Spruce-fir
100
90
75
60
45
30
15
0
White-redjack pine
150
Oak-gumcypress
200
2002
Lodgepole
pine
250
Million acres
Million acres
300
5
1977
Oak-pine
350
90
75
60
45
30
15
0
HemlockSitka spruce
Alaska
Loblollyshortleaf
pine
Pacific Coast
Fir-spruce
Rocky Mtn.
Ponderosa
pine
South
400
Douglas-fir
North
Extent of Area by Forest Type Relative to Total Forest Area
Million acres
Indicator 1.
Figure 1-1. Area of forest land by region, 1630–2002.
Figure 1-2. Forest by major type in the United States, 1977
and 2002 (excluding Alaska).
What Is the Indicator and Why Is It Important?
Broadleaf forests. At 132 million acres, oak-hickory
(Quercus/Carya spp.) is the largest single forest cover
type. It constitutes more than 17 percent of all forest
land in the Nation and nearly half of all broadleaf
forests. Covering 55 million acres, maple-beech-birch
forests (Acer/Fagus/Betula spp.), are also dominant in
the Eastern United States. Combined, these two
upland forest types constitute nearly two-thirds of all
broadleaf forests, which have increased 18 and 42
percent, respectively, since 1977.
Forest type is a coarse representation of land cover
based on major tree species associations. As individual
trees respond to natural or human-induced change,
forest composition and structure change. Monitoring
changes in the location and distribution of forest types
is useful for resource managers and analysts interested
in forest resources to track the sustainability and
diversity of the Nation’s forest cover and the desired
future condition of that forest cover.
Conifer forests. Pines (Pinus spp.) are the single-most
dominant group of conifer forests. Loblolly-shortleaf
pine (P. taeda, echuinata) and longleaf-slash pine
(P. palustris, elliotii) types in the South and ponderosa
and lodgepole pine types (P. ponderosa and contorta) in
the West combine to cover 115 million acres, or more
than one-fourth of all conifer forest types. The largest
single conifer type, with 61 million acres in interior
Alaska, is the spruce-birch (Picea/Betula spp.) type.
Douglas-fir (Pseudotsuga menzezii) follows closely, with
40 million acres found predominantly in the
Pacific Coast Region.
The current forest area in the United States is 749
million acres, or about one-third of the Nation’s land
area. The U.S. forest area was about 1 billion acres at
the time of European settlement. Of the total forest
land loss of 300 million acres, most (nearly 200 million
acres) occurred in the East (North and South regions)
between 1850 and 1900, with the loss consisting predominantly of broadleaf forest cleared for agriculture.
For the last 100 years, the total forest area has been
relatively stable, while the U.S. population has more
than doubled. Today, conifer forests cover 412 million
acres in the United States and are found predominantly
in the West (315 million acres) and South (67 million
acres). Broadleaf forests cover 273 million acres, and
are located predominantly in the North and South (223
million acres).
Mixed forests. Virtually all mixed forests of oak-pine
(Quercus/Pinus spp.) and oak-gum-cypress
(Quercus/Nyssa/Taxodium spp.), with 59 of the 64
million total acres, are found in the South. While oakgum-cypress is found in the wet lowlands of the
South, oak-pine is usually found on the drier uplands.
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