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The biomass resources of the United States are distributed across a land area of approximately 2.3 billion acres. Beginning in northern Alaska and extending to the Mexican border, this land base includes a wide variety of climates, soils, vegetation types and topographic features. It is the local interaction of these factors that makes any given land area more suitable for some uses than for others. The most recent land use census found the predominant uses of land in 2002 consisted of forest use, grassland pasture and range, and cropland. Urban land made up just 3% of the total U.S. land area, while national and state forests, wilderness and wildlife areas, along with national defense installations and other special use lands, together made up about 10% (figure 1). Of all these types of land use, the largest contributors to the biomass resources of the U.S were the agriculture and forestry sectors.

Agriculture   Agriculture currently produces the largest share of biomass crops, such as corn for ethanol and soybeans for biodiesel, as well as new crops already in use or under evaluation as sources of biomass energy and bioproducts.   The major crops produced on U.S. cropland in 2002 were corn (69 million acres), soybeans (72.5 million acres), wheat (50 million acres), alfalfa (22 million acres), other hay (38 million acres), and cotton (13 million acres). The remaining crop acres were in miscellaneous grain and oil seed crops, and fruits and vegetables.    At present, corn, soybeans, alfalfa and other hay are produced primarily for livestock feed. However, a significant and increasing portion of corn production is currently used to produce bioenergy and bioproducts. In 2005, about 2 billion bushels of corn were used to produce some 4 billion gallons of fuel ethanol. Corn is also used to produce bioproducts, such as polylactic acid (biodegradable plastic) and 1,3-propanediol, used to produce Sorona®, a synthetic fabric.   Soybean oil currently goes mainly to food uses. However, industrial uses include soybean oil used to produce biodiesel - 30 million gallons in 2004, using about 20 million of the U.S. total 1.65 billion soybean bushel production. About 4% of the soybean oil produced in 2004 was used to produce bioproducts such as inks, adhesives and binders, plastics and detergents, among others. Forestry   Wood and forest product residues are increasingly used to produce both bioproducts and bioenergy. The most recent forestry census showed nearly a third of the land area of the United States covered by forests. Some 57% percent of all U.S. forest land is privately owned. Public forest land dominates in the western U.S. where large tracts of federal land went unclaimed by early homesteaders, while private forest land is predominant in the East (figure 3).                 Approximately 57% of growing stock in U.S. forests consists of softwood, with the remaining 43% in hardwoods. Nearly 90% of total hardwood timber lies in the Eastern United States. Hardwoods are used mostly for lumber and other construction products, while pine and other softwoods are used primarily for paper and pulp. Trends in U.S. Land Use   Among the most consistent trends in major uses of land have been an upward trend in special-use and urban areas, and a downward trend in cropland and total grazing land. Between 1997 and 2002, total U.S. cropland area declined by almost 14 million acres (3%). Much of this decline took place in Eastern states where the expansion of urban areas has encroached on farmland, resulting in the permanent loss of cropland to housing, commercial development and other urban uses. Forest-use land increased about 1% between 1997 and 2002, reversing an earlier decline. Most of this increase took place in the Western states as a result of citizen conservation movements.