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The United States has a land area of about 2.3 billion
acres, which can be categorized as:
- Rural (2.2 billion acres, or 97 percent)
includes agricultural (range, cropland, pasture,
farmsteads, and roads), forest, and other land.
- Urban (60 million acres; 3 percent)
includes residential, commercial, utilities,
mixed, transitional, and other urban land.
Major uses of land in 2002 were:
- Cropland, 442 million acres (20 percent of the land
area)
- Grassland pasture and range, 587 million acres (26
percent)
- Forest-use land (total forest land exclusive of forested
areas in parks and other special uses), 651 million
acres (19 percent)
- Special uses (parks, wilderness, wildlife, and related
uses), 297 million acres (13 percent)
- Urban land, 60 million acres (3 percent)
- Miscellaneous other land (deserts, wetlands, and
barren land), 228 million acres (10 percent).
These proportions vary greatly from region to region due
to differences in climate, geography, and population levels.
For example, the Northeast has 12 percent of its area
in cropland, compared with 58 percent in the Corn Belt.
However, nearly 60 percent of the Northeast is in forest
compared with only 2 percent in the Northern Plains.
National and regional proportions are also skewed by
the land area of Alaska, which has very little cropland
and pasture but large areas of forest-use, special-use,
and miscellaneous other land.
Changes in Major Uses
Major land uses have changed little, in percentage terms,
between 1997 and 2002, for the 48 contiguous States. Because
Alaska and Hawaii have very little crop area, the discussion
in this section focuses on the contiguous 48 States.
The largest acreage change from 1997 to 2002 was a 13-million-acre
decrease in cropland (-3 percent). This continues a long
downward trend from 1978, when cropland totaled 470 million
acres, an overall 6-percent drop. Total cropland area
in 2002 was at 442 million acres, its lowest point since
in 1945, but only 2 million acres (less than 1 percent)
below the previous low in 1964. Cropland has been relatively
constant from 1945 to 1997, ranging between 442 and 471
million acres and averaging about 463 million acres.
While land defined as forest use has been on a declining
trend from 612 million acres in 1964, forest-use lands
increased from 552 to 559 million acres between 1997 and
2002. Forest-use land excludes forested areas in special
uses, estimated at 98 million acres in 2002.
Estimated acreage of grassland pasture and range increased
by over 6 million acres (1 percent) between 1997 and 2002.
However, total land used for grazing (the combined acreage
of cropland pasture, grassland pasture and range, and
grazed forests) decreased from 786 to 780 million acres
during 1997-2002, continuing a steady downward trend since
the 1940s.
Miscellaneous uses—marshes, swamps, bare rock areas,
deserts, and transitional areas—decreased 6 million
acres (-6 percent). This is a residual category that includes
land not in any of the other major land use categories.
The decline in miscellaneous use areas from 1997 to 2002
may have been due to a reclassification of these lands
as "special use" areas, which increased by 11
million acres (8 percent) from 1997 to 2002.
The parks and wildlife component of special uses increased
5 million acres (5 percent) from 1997 to 2002. The remaining
change was the result of an estimated 2-million acre increase
in rural transportation areas and a 4-million acre increase
in farmsteads/farm roads. These changes reflect, at least
in part, the availability of new data and the use of improved
estimation methods in 2002 rather than an actual change
in acreage over 1997-2002.
Urban
area is estimated at 60 million acres in 2002, compared
to an estimated 66 million acres in 1997. This decline
in the estimates is due to changes in the way urban land
area is measured and provides little information on changes
in urbanized area from 1997 to 2002. Rural
residential land, a new land use category introduced
in 1997, was estimated to be about 94 million acres in
2002, up from the 1997 estimate of 83 million acres.
Factors Contributing to Land
Use Change
Several economic, demographic, technological, and policy
factors influence land use dynamics. According to land
rent theory, allocation among competing uses on a fixed
land base is determined by the associated land rents,
which vary according to land quality and location. Land
is allocated to the use with the highest return. As relative
rents change over time, land use would shift between uses.
For example, land has shifted into crop production from
other uses in response to rising commodity prices. However,
land-use changes are gradual due to conversion costs.
Between 1945 and 2000, the U.S. population doubled from
133 million to 281 million people. In 2000, there were
106 million households, a quarter of which were one-person
households. More land was converted to urban uses, especially
for homes. New residential uses also require land
for schools, office buildings, shopping sites, and other
commercial and industrial uses. The amount of land converted
to urban use rose steadily from 15 million acres in
1945 to an estimated 60 million acres in 2002. These increases
came mostly from pasture, range, and forest land.
Technology has also affected land use and regional land-use
shifts, especially in cropland. The rapid adoption
of new technology, improved crop varieties, improved
insect and disease control, and other changes have boosted
agricultural productivity
so that more production can be obtained from the same
cropland base. Agricultural productivity has more than
doubled over the past 50 years.
Larger farm equipment and increased use of irrigation
has favored regions with large, level fields. Thus, crop
production declined in the Northeast, Appalachian, and
Southeast regions. Changes in use of land for high-value
crops, especially vegetables, is particularly evident
in the developing fringes of major metropolitan areas.
Urbanized area accounted for only 2.6 percent of the
U.S. land base in 2002. Nevertheless, urban influence
affected about 17 percent of the Nation's agricultural
land in 1997. Farms near urban areas realize higher land
values, giving farmers an incentive to sell farmland for
nonfarm development. Local, State, and Federal governments
have increased their efforts toward preserving agricultural
lands and their associated rural
amenities.
Federal agricultural commodity and conservation policies
and State and local land-use programs have influenced
land use both within agriculture and between agriculture
and other uses. For example, while commodity
programs, such as income support programs and acreage
set-aside, helped to sustain or increase cropland acreage,
at its peak in 1992-95, the Conservation
Reserve Program took about 36 million acres of land
out of crop production.
The 1996 Federal Agriculture Improvement and Reform (FAIR)
Act ended authority for annual acreage reduction programs
and decoupled income support payments from land-use decisions,
allowing producers to change land use without jeopardizing
program payments. The 2002
Farm Act updated crop acreage bases to the 1998-2001
period.
Trends in the use of U.S. Cropland
Cropland
used for crops consists of:
- Crop failure
- Summer fallow
- Cropland harvested
Crop Failure
Cropland failure increased sharply in 2002.
- Cropland failure, 15 million acres, was the largest
since 1956.
- Drought in the Great Plains States was the major cause.
All the Plains states had significant acreages of crop
failure. Texas reached a high of 2.6 million acres (11
percent of planted acres). Colorado had the highest percent
failure rate-16 percent if planted acres. North Dakota,
South Dakota, Nebraska, Kansas, Oklahoma, and New Mexico
also had high crop failure rates.
High crop failure rates in 2002 were not
limited to the Great Plains States. In the southeast,
South Carolina, Georgia, and Alabama also had high failure
rates, ranging from 6.5 to 11.4 percent.
The U.S. national average was 4.4 percent,
higher than many states, but much lower than the Plains
states. The 2002 failed acreage of 15 million acres, while
high, pales in comparison to the 1930's Great Depression
years. In 1934, during drought and Dust Bowl conditions,
64 million acres of planted cropland
failed.
Summer Fallow
The use of summer fallow as a moisture-conserving crop
production practice continues to decline. Summer fallow
reached a high of 41 million acres in 1969 and has since
declined to 19 million acres in 2002. The decline is partly
attributed to the adoption of other moisture-conserving
soil conservation practices, such as no-till and mulch-till,
which have reduced the need for summer
fallow.
Some of the decrease in summer fallow may also be attributable
to the Conservation Reserve Program. Much of the CRP is
in the Great Plains where summer fallow is most commonly
practiced. Land taken out production and placed in the
CRP includes some land that might otherwise have been
in summer fallow.
Harvested Cropland
Cropland has remained relatively stable over the past
10 years. The biggest change has been a decrease in cropland
idled by Federal
programs.
Together, harvested cropland, crop failure, and summer
fallow accounted for 340 million acres of cropland used
for crops in 2002, unchanged from 2001. This is down 1
million acres from the 1993-2000 average of 341 million
acres.
Cropland used for crops increased dramatically in 1996,
the year the Federal Agriculture Improvement and Reform
(FAIR) Act took effect. Under the FAIR Act, land previously
set aside in Federal acreage reduction programs became
available for crops. Since 1997, however, cropland used
for crops has gradually decreased from a high of 349 million
acres to 340 million acres, primarily due to low commodity
prices.
The decrease in cropland used for crops reflects lower
harvested acres of wheat and, to a lesser degree, sorghum,
barley, oats, and cotton. Wheat
acreage declined 17 million acres from 1996 to 2002.
Cropland idled in Federal programs has decreased about
21 million acres since 1995 with the elimination of annual
commodity programs and changes to the Conservation Reserve
Program (CRP).
Harvested cropland fluctuated from a low of 297 million
acres in 1993 to a high of 321 million acres in 1997 and
declined to 307 million acres in 2002.
Most cropland used for crops is harvested, but typically
2-4 percent experiences crop failure and 5-8 percent is
cultivated as summer fallow to build moisture for the
following year. In 2002, farmers harvested one or more
crops on an estimated 307 million acres of cropland, down
4 million acres from 2001. This was largely a result of
reduced hay, wheat, sorghum, rice, and cotton acres. About
10 million acres of the total acres harvested were double-cropped.
When double-cropped land is counted twice, harvested land
increases to over 317 million acres. Four crops—corn
for grain, soybeans, wheat, and hay—account for 80.2
percent of all crop
acres harvested in 2002. An additional 15 principal
crops accounted for another 15.2 percent of harvested
area. Vegetables, fruits, nuts, and all other crops accounted
for the remaining 4.7 percent of crop area harvested in
2002.
In 2002, harvested acreage of corn, hay, dry beans,
sugar beets, and oats increased. The acreage of sorghum,
barley, wheat, soybeans, cotton, and rice decreased. The
decrease in harvested wheat acreage, most of it in the
Great Plains, was largely responsible for the overall
decline in harvested cropland.
- Harvested wheat acreage in 2002 was the lowest since
1970. This was probably due to several factors, including
low wheat prices, more profitable alternative crops,
and the success of the CRP taking acreage out of production.
- Soybean acreage harvested in 2002 was down slightly
after reaching an all-time high in the United States
of 73 million acres in 2001.
- Corn acreage increased from the 1960s to the early
1980s, decreased for a few years, and trended upward
again in the late 1980s and early 1990s. Corn acreage
was up about 1 percent from 2001 to 2002.
- Sorghum and barley fluctuated year to year until
the mid-1980s, when they increased to 30-year highs.
Both crops have declined since 1986.
- Harvested rice acreage in 2002 decreased about 3
percent from 2001.
- The 2002 peanut acreage is the lowest it has been
since 1982.
- Rye acreage has declined fairly consistently over
the last 50 years.
- Sunflower production increased until the early 1980s,
declined for a few years, and increased again in the
1990s. Acreage has trended downward again from 2000
to 2002.
- Oats have trended down over the last 30 years, while
acreage of all hay has changed very little.
- Harvested acreage of cotton hit a low of less than
8 million acres in 1983 and has since trended up toward
the higher levels of the late 1970s.
- Tobacco has trended downward over the last 50 years.
- Lower demand for cooking oils has led to decreased
production of special oilseed crops. Special oilseeds
include canola, safflower, and sunflower seed. Special
oilseed crops decreased from 4.6 million acres in 1996
to 3.7 million acres in 2002.
- Several other principal crops—dry edible beans
and peas, potatoes, and sugar beets—occupy a comparatively
small acreage and have exhibited no major trends.
- Federal commodity programs, until 1996, promoted
the production of industrial and other crops by allowing
these crops to be planted on acreage diversion program
lands. The crops allowed in 1995 included castor beans,
chia, crambe, crotalaria, cuphea, guar, guayule, hesperaloe,
kenaf, lesquerella, meadowfoam, milkweed, plantago ovato,
and sesame. Deficiency payments were not reduced when
these crops were planted on diverted acreage.
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