Timberland

In 1992, nearly 393 million acres of timberland, or about four-fifths of the nation's total, was considered to be nonfederal timberland (Table A-3). Nonfederal timberland is forestland that is capable of producing more than 20 cubic feet of wood per acre per year and that is not withdrawn from timber utilization by statute or regulation. The nation's nonfederal timberland has increased modestly since 1952, having peaked at slightly more than 396 million acres in 1962. Regionally, nonfederal timberland is concentrated in the South, with 183 million acres or 47 percent of the national total. The Northeast and North Central regions contain 20 percent and 18 percent of nonfederal timberland, respectively. The least amount of nonfederal timberland is located in the Rocky Mountain region, with about 23 million acres or 6 percent of the total.

Conversion to Non-Forest

A variety of conditions can influence the size of nonfederal forestland area. Afforestation and reforestation can increase the area; urbanization might simply change the character of the forest and its predominate use without diminishing its size. But habitat conversion and forest fragmentation can affect forest size and character.

According to USDA NRCS estimates of land use (not forest cover), the net amount of forestland in the conterminous 48 states has remained relatively constant between 1982 and 1992 (Table A-4). However, of the estimated 395 million acres of nonfederal forestland in 1982, nearly 5.6 million acres was diverted to developed uses, 2.9 million acres to pastureland, and 1.5 million acres to cropland. Developed uses include urban and built-up areas and rural land used for transportation-related purposes (USDA Soil Conservation Service 1991). Another 2.4 million acres were converted to water areas or diverted to federal lands. In all, 14.8 million acres, or 4 percent, of nonfederal forestland were converted to other uses during the decade from 1982 to 1992. During the same period, an additional 15.4 million acres became part of the nonfederal forestland base (Table A-4). The vast majority of the additions came from pastureland (8.2 million acres) and cropland (3.1 million acres). Smaller additions came from water areas and federal land (0.8 million acres) and developed land (0.2 million acres).

Urban and Community Forestland

Urban and community forestland is increasingly recognized as an important component of the nation's forestland. However, the actual amount of forest cover in urban and community areas is uncertain, in part because of disagreement about what constitutes an urban and community forest. For example, forest ecosystems located in the center of urban areas, in the suburbs around these areas,



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