An Analysis of the Land Base Situation in the
United States: 1989-2040
A Supporting Technical Document to the 1989 RPA
Assessment
HIGHLIGHTS
In 1987, 1.5 billion acres, about 63% of the total land and inland water
area of the United States, was in forest and rangeland. Forest totals 32% and rangeland
totals 34% of the land area. Most of the Nation's forest and rangeland are in nonfederal
ownership.
In 1987, about 1 billion acres or 67% of the total were owned by
nonfederal public agencies, forest industry, farmers and ranchers, and other private
individuals. The nonfederal forest lands are concentrated in the East, and private
rangelands are concentrated in the West. The federal lands are administered primarily by
two agencies - the Forest Service and the Bureau of Land Management.
Most of the Nation's high productivity forest lands are located west of
the Cascade Mountains in the Pacific Northwest Region and in the South Central Region. The
largest areas of highly productive sites are covered by coastal Douglas-fir and
hemlock-Sitka spruce types in the West, and loblolly-shortleaf pine and oak-gum-cypress
types in the East.
The North and the Great Plains
The 606.7 million acres of land in the North and Great Plains include
169.8 million acres of forest land, 28% of the total. Much of this forest land, especially
in the Northeast, lies close to densely populated areas and receives intense pressure from
a wide array of forest users.
The oak-hickory ecosystem is the largest in the area, with 47.8 million
acres of unreserved forest land, or 29% of the total. Maple-beech-birch is the second
largest with 43.4 million acres, followed by spruce-fir with 18.9 million acres,
aspen-birch with 17.9 million acres, white-red-jack pine with 13.5 million acres, and
elm-ash-cottonwood with 11.9 million acres.
Although there is much variation among states, about 80% of all
timberland in the North and Great Plains is held by private individuals or firms. Farmers
own more forest land than any other group of individual owners.
The area of timberland in New England and the Middle Atlantic states
increased steadily from 1952 to 1987. In the North Central Region and Great Plains Region,
trends are mixed. A total of 79 million acres in the North and Great Plains are classified
as rangeland, almost all in the Great Plains. Ninety-five percent of the rangeland is in
nonfederal ownership.
Water areas in the North and Great Plains total 57.8 million acres or
54% of the Nation's water. This is 8.7% of the land and water area of the two Regions.
The South
Forest land totals nearly 200 million acres or 38% of the total land
area. If the nontimbered western portion of Texas and Oklahoma are excluded, the
percentage of forest increases to 54%. The South's 62 million acres of pine forest
continue as a major source of softwood fiber for the world. About two-thirds of the pine
forest is natural in origin, with the remainder consisting of planted pine.
Loblolly-shortleaf pine is the South's most prevalent pine ecosystem,
accounting for three-fourths of the total pine forest or 46 million acres. Longleaf-slash
pine totals 16 million acres and the oak-pine type covers 28 million acres. Oak-hickory is
the South's most extensive ecosystem, covering 71 million acres. Bottomland hardwood types
cover 31 million acres.
Private owners control 90% of the timberland in the South, a total of
175 million acres. Nonindustrial private owners control 70% of the South's timberland, and
forest industry owners control 20%. The South has 116 million acres of rangeland, with 83%
in Texas and the remainder in Oklahoma and Florida. Water areas in the South cover 24
million acres, or 4% of the total area in the Region.
The Rocky Mountains
More than 138 million acres or about 25% of the land area are occupied
by forests, predominantly of softwood species. Five forest ecosystems totaling some 112
million acres make up about 80% of the forest land in the Rocky Mountain Region -
pinyon-juniper, Douglas-fir, fir-spruce, ponderosa pine, and lodgepole pine.
The ponderosa pine ecosystem covers about 16.5 million acres, nearly
half of which is in Arizona and New Mexico. Douglas-fir covers 17.9 million acres,
primarily in Idaho and Montana. Lodgepole pine covers 14.6 million acres, principally in
Idaho, Montana, Wyoming, and central Colorado. Fir-spruce covers 16 million acres of
higher elevation sites in the region. Pinyon-juniper is a woodland ecosystem covering
about 47 million acres of dry plateaus and broken tablelands. Three-fourths of the forest
land in the Rocky Mountain region is publicly owned. Federal agencies, primarily the
Forest Service, administer 94 million acres or two-thirds of the total.
The total rangeland area, including pinyon-juniper and
chaparral-mountain scrub forests, is about 336 million acres, or 61% of the total land
base. The sagebrush type is the second largest range ecosystem in the United States, with
roughly 105 million acres occurring mostly in the Rocky Mountain Region. Other important
rangeland types include sagebrush, southwestern shrubsteppe, desert shrub, mountain
grasslands, and plains grasslands. About 167.4 million acres or 50% of the rangeland in
the Rocky Mountain Region are in public ownership, mostly in the care of the Bureau of
Land Management.
The Rocky Mountain Region has the smallest water area - roughly 6
million acres or 1% of the total geographic area.
The Pacific Coast
Forests cover 220 million acres or 39% of the land area of the Pacific
Coast states. This is 30% of all the forest land in the nation. Productive timberland
totals about 85 million acres and other forest land about 135 million acres. Douglas-fir,
the most important forest type in terms of timber production, covers about 21 million
acres. It is the major timber type in western Oregon and western Washington.
Fir-spruce is the most extensive forest type, covering about 116 million
acres, mostly in Alaska's interior. Hemlock-Sitka spruce covers about 16 million, 11
million of which are located in southeastern Alaska. The redwood type covers about 1.2
million acres in California. The ponderosa pine type cover about 14 million acres of the
Pacific Coast, and lodgepole pine covers about 3.6 million acres. The pinyon-juniper
woodland type cover about 5 million acres, and chaparral covers about 7.6 million acres,
mostly in the mediterranean climatic zone in California.
Of the 220 million acres of forest land in the 5-state area, 72 million
are privately owned. Of the 145 million acres in public ownership, 46 million acres are in
national forests and 99 million acres are held by various other public agencies. Ownership
of forest land in Alaska has changed dramatically in the last decade.
Alaska has about 173 million acres of rangeland, most of which is arctic
and alpine tundra. California, Oregon, and Washington together have about 68 million acres
of rangeland including 23 million acres of grassland and 45 million acres of shrubland.
The Pacific Coast states contain 20.1 million acres of water, much of which is in coastal
waterways.
Projecting Land Cover and Use Changes
The total area of forest and rangeland is projected to increase about 2%
between 1987 and 2000, and then to decrease slightly by 2040. The area of forest land is
projected to decline over the projection period, decreasing by 4% by 2040. The projected
reduction in forest land area will result mainly from conversion to other land uses such
as reservoirs, urban expansion, highways, and surface mining.
The projected average annual reduction in United States forest area from
1987 to 2040, about 500,000 acres, is less than that for the period 1970 to 1987, which
averaged about 2 million acres per year. Approximately 40 to 45 million acres of highly
erodible land used currently for cropland are projected to be converted to grass cover or
trees under the Conservation Reserve Program by the year 2000.
In the North and Great Plains, forest and range area is projected to
decline. In the Rocky Mountains, total forest and range area is expected to increase by
about 15 million acres by 2040, mostly due to expansion of range area. In the Pacific
Coast, forest area is projected to drop by about 8 million acres and range area is
expected to drop by 9 million acres by 2040.
USDA Forest Service. 1989. An Analysis of the Land Base Situation in the
United States: 1989-2040. General Technical Report RM-181. Fort Collins, CO: U.S.
Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment
Station. 76 p.