EPA's Report on the Environment
Definitions of Land Use Categories
NRI (USDA NCRS, 2009)
Developed land. A combination of the land use categories large urban and built-up areas, small built-up areas, and rural transportation land.
- Urban and built-up areas. A land use category consisting of residential, industrial, commercial, and institutional land; construction sites; public administrative sites; railroad yards; cemeteries; airports; golf courses; sanitary landfills; sewage treatment plants; water control structures and spillways; other land used for such purposes; small parks (less than 10 acres) within urban and built-up areas; and highways, railroads, and other transportation facilities if they are surrounded by urban areas. Also included are tracts of less than 10 acres that do not meet the above definition but are completely surrounded by urban and built-up land. The NRI recognizes two size categories:
- Small built-up areas. Areas that meet the definition of urban and built-up areas consisting of developed land units of 0.25 to 10 acres.
- Large urban and built-up areas. Areas that meet the definition of urban and built-up areas composed of developed tracts of at least 10 acres.
- Rural transportation land. A land use category that consists of all highways, roads, railroads and associated right-of-ways outside urban and built-up areas; it also includes private roads to farmsteads or ranch headquarters, logging roads, and other private roads (field lanes are not included).
Cropland. A land use category that includes areas used for the production of adapted crops for harvest. Two subcategories of cropland are recognized: cultivated and noncultivated. Cultivated cropland comprises land in row crops or close-grown crops, as well as cultivated land (for example, hayland or pastureland) that is in a rotation with row or close-grown crops. Noncultivated cropland includes permanent hayland and horticultural cropland.
- Hayland. A subcategory of cropland managed for the production of forage crops that are machine-harvested. The crop may be grasses, legumes, or a combination of both. Hayland also includes land in setaside or other short-term agricultural programs.
- Horticultural cropland. A subcategory of cropland used for growing fruit, nut, berry, vineyard, and other bush fruit and similar crops. Nurseries and other ornamental plantings are included.
Pastureland. A land use category of land managed primarily for the production of introduced forage plants for livestock grazing. Pastureland cover may consist of a single species in a pure stand, a grass mixture, or a grass-legume mixture. Management usually consists of cultural treatments: fertilization, weed control, reseeding or renovation, and control of grazing. For the NRI, this category includes land that has a vegetative cover of grasses, legumes, and/or forbs, regardless of whether or not it is being grazed by livestock.
FIA (Smith et al., 2009)
Forest land. Land at least 120 feet wide and 1 acre in size with at least 10 percent cover (or equivalent stocking) by live trees of any size, including land that formerly had such tree cover and that will be naturally or artificially regenerated. Forest land includes transition zones, such as areas between forest and nonforest lands that have at least 10 percent cover (or equivalent stocking) with live trees and forest areas adjacent to urban and built-up lands. Roadside, streamside, and shelterbelt strips of trees must have a crown width of at least 120 feet and continuous length of at least 363 feet to qualify as forest land. Unimproved roads and trails, streams, and clearings in forest areas are classified as forest if they are less than 120 feet wide or an acre in size. Tree-covered areas in agricultural production settings, such as fruit orchards, or tree-covered areas in urban settings, such as city parks, are not considered forest land.
Timber land. Forest land that is producing or is capable of producing crops of industrial wood and not withdrawn from timber utilization by statute or administrative regulation. Areas qualifying as timber land are capable of producing in excess of 20 cubic feet per acre per year of industrial wood in natural stands. Currently inaccessible and inoperable areas are included.
ERS (Nickerson et al., 2011)
Grassland pasture and range. Grassland pasture and range encompass all open land used primarily for pasture and grazing, including shrub and brushland types of pasture, grazing land with sagebrush and scattered mesquite, and all tame and native grasses, legumes, and other forage used for pasture or grazing—regardless of ownership. Because of the diversity in vegetative composition, grassland pasture and range are not always clearly distinguishable from other types of pasture and range. At one extreme, permanent grassland may merge with cropland pasture, or grassland may often be found in transitional areas with forested grazing land. ERS data are composites of data from the National Resources Inventory (NRI), the Census of Agriculture, the Bureau of Land Management, the USDA Forest Service, and several other federal agencies.
Forest land grazed. Forested pasture and range consisting mainly of forest, brush-grown pasture, arid woodlands, and other areas within forested areas that have grass or other forage growth. The total acreage of forested grazing land includes woodland pasture in farms plus estimates of forested grazing land not in farms. For many states, the estimates include significant areas grazed only lightly or sporadically. The Census of Agriculture, the NRI, and the USDA Forest Service data on active grazing allotments are the principal sources of data.
Cropland pasture. Land generally considered to be in long-term crop rotation. This category includes acres of crops hogged or grazed but not harvested, as well as some land used for pasture that could have been cropped without additional improvement. Cropland pastured before or after crops were harvested is defined as harvested cropland and not cropland pasture. Estimates in this land use category are derived from the Census of Agriculture.
Grazing land. This is the sum of three other categories: grassland pasture and range, forested land grazed, and cropland pasture.
NASS (USDA NASS, 2009)
Total cropland (labeled “Cropland” in ROE exhibits). This category includes cropland harvested, cropland used only for pasture or grazing, cropland on which all crops failed or were abandoned, cropland in cultivated summer fallow, and cropland idle or used for cover crops or soil improvement but not harvested and not pastured or grazed.
Cropland used only for pasture or grazing (labeled “Cropland pasture” in ROE exhibits). This category includes land used only for pasture or grazing that could have been used for crops without additional improvement. Also included are acres of crops hogged or grazed but not harvested before grazing. However, cropland that was pastured before or after crops were harvested in 2007 is included as harvested cropland rather than cropland for pasture or grazing.
Permanent pasture and rangeland, other than cropland and woodland pastured (labeled “Pastureland and rangeland” in ROE exhibits). This land use category encompasses grazable land that does not qualify as woodland pasture or cropland pasture. It may be irrigated or dry land. In some areas, it can be a high-quality pasture that could not be cropped without improvements. In other areas, it can barely be grazed and is only marginally better than wasteland. Before the 2007 Census of Agriculture, this category was referred to as “pastureland and rangeland, other than cropland pastured.” This is a wording change only; all data are comparable.
Nickerson, C., R. Ebel, A. Borchers, and F. Carriazo. 2011. Major uses of land in the United States, 2007. EIB-89, U.S. Department of Agriculture, Economic Research Service, December 2011. http://www.ers.usda.gov/publications/eib-economic-information-bulletin/eib89.aspx.
Smith, W.B., P.D. Miles, C.H. Perry, and S.A. Pugh. 2009. Forest resources of the United States, 2007. Gen. Tech. Rep. WO-78. Washington, DC: U.S. Department of Agriculture, Forest Service, Washington Office. http://www.fs.fed.us/nrs/pubs/gtr/gtr_wo78.pdf (PDF) (349 pp, 12.7MB).
USDA NASS (United States Department of Agriculture, National Agricultural Statistics Service). 2009. 2007 census of agriculture: United States summary and state data. February 2009; updated December 2009. Report AC-07-A-51. http://www.agcensus.usda.gov/Publications/2007/Full_Report/usv1.pdf (PDF) (739 pp. 6.4MB).
USDA NCRS (United States Department of Agriculture, Natural Resources Conservation Service). 2009. Summary report: 2007 National Resources Inventory. http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb1041379.pdf (PDF) (127 pp, 1.8MB).