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Percent of Non-Federal Area in Prime Farmland, 1992
Description
This map shows the spatial distribution of the
nation's non-Federal prime farmland in 1992 as a
percentage of the total non-Federal land area
for each 8-digit hydrologic unit. Nationwide
335,482,200 acres of non-Federal area are prime
farmland. Areas with 95% or more federal area
are shaded gray.
Cautions for this Product:
Use this map only to identify broad spatial
trends. 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 is shown by 6-digit hydrologic unit.
Sources
Source:
National Resources Inventory, 1997
Distributor:
USDA-NRCS-RIAD
Reliability:
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.
Layers
Aggregate Layer:
8 Digit Hydrologic Unit Areas with Federal Land
Other Layers Displayed:
Rivers, States
Definitions
Non-Federal land:
Includes all land and water areas where the
ownership is by private, municipal, county or
parish, state, Indian tribal, individual trust,
the Tennessee Valley Authority, or areas under
temporary control of a Federal, state, county or
municipal agency or government for foreclosure
or nonpayment of taxes.
Prime farmland:
Land that has the best combination of physical
and chemical characteristics for producing food,
feed, forage, fiber, and oilseed crops and is
also available for these uses. It has the soil
quality, growing season, and moisture supply
needed to produce economically sustained high
yields of crops when treated and managed
according to acceptable farming methods,
including water management. In general, prime
farmlands have an adequate and dependable water
supply from precipitation or irrigation, a
favorable temperature and growing season,
acceptable acidity or alkalinity, acceptable
salt and sodium content, and few or no rocks.
They are permeable to water and air. Prime
farmlands are not excessively erodible or
saturated with water for a long period of time,
and they either do not flood frequently or are
protected from flooding.[SSM, USDA Handbook No.
18, October 1993]
Product Information
Product ID:
5871
Production Date:
1/12/01
Product Type:
Map
For additional information
contact the Resources Inventory and Assessment Division.
Please include the Product ID you are inquiring about.
nri@wdc.usda.gov
or 1400 Independence Avenue SW - P.O. Box 2890 -
Washington D.C. 20013. If you use our analysis products,
please be aware of our disclaimer.
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