Acres of Cropland, 1987
This dot density map shows the distribution of cropland. Dots are aggregated by and placed randomly within 8-digit hydrologic units. Each green dot represents 25,000 acres of cropland. Areas with 95% or more Federal area are shaded gray. There were 406.6 million acres of cropland in the U.S. in 1987.
Cautions for this Product:
This map may not be used to determine site- specific information. Within an 8-digit hydrologic unit, dot counts represent acreage totals correctly plus or minus one dot to account for remainders. Data are not collected on Federal land. Data are not available for Alaska or the Pacific Basin. Data for Puerto Rico and the U.S. Virgin Islands are aggregated by 6-digit hydrologic unit.
Source: National Resources Inventory, 1997
NRI sample data are generally reliable at the 95% confidence interval for state and certain broad substate area analyses. Generally, analyses that aggregate data points by smaller geographic areas and/or more specific criteria result in fewer data points for each aggregation and therefore less reliable estimates. NRI maps reflect national patterns rather than site- specific information.
Aggregate Layer: Cross of State with 8 Digit Hydrologic Units and Federal Land
Other Layers Displayed: States, Rivers
A Land cover/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 and also other cultivated cropland, for example, hayland or pastureland that is in a rotation with row or close-grown crops. Noncultivated cropland includes permanent hayland and horticultural cropland. [NRI-97]
Includes land identified as being in row or close crops, summer fallow, aquaculture in crop rotation or other cropland not planted -- including cropland in short-term set-aside programs; or land in horticulture that is double cropped; or land in hay which had at least one of the three previous years in row or close grown crops; or land in pasture which had at least one of the three previous years in row or close grown crops.
Includes land in horticulture that is not double- cropped; or land in hay which had not been in row or close-grown crops for any of the previous three years.
Product ID: 5975
Production Date: 5/25/01
Product Type: Map
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