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Acres of Prime Farmland Converted to Developed Land, 1982-1997
Description
This dot density map shows the general
distribution of prime farmland acreage that was
lost to development from 1982 to 1997. Each dot
represents 2,000 acres that were lost.
Developed land includes both urban and built-up
areas and rural transportation land. Dots were
aggregated by and placed randomly within 8-digit
hydrologic units. Data were not collected on
Federal land.
Cautions for this Product:
This map may not be used to determine site-
specific information.
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:
Cross of State with 8 Digit Hydrologic Units and
Federal Land
Other Layers Displayed:
State
Definitions
Federal land:
A land ownership class designating land that is
owned by the Federal Government. It does not
include, for example, trust lands administered
by the Bureau of Indian Affairs nor Tennessee
Valley Authority (TVA) land. No data are
collected for any year that land is in this
ownership. [NRI-97]
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]
Rural transportation land:
A Land Cover/Use category which consists of all
highways, roads, railroads and associated rights-
of-way outside urban and built-up areas;
including private roads to farmsteads or ranch
headquarters, logging roads, and other private
roads, except field lanes. [NRI-97]
Urban and built-up areas:
A Land Cover/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. Two size categories are recognized in the
NRI: (i) areas 0.25 to 10 acres, and (ii) areas
greater than 10 acres. [NRI-97]
Product Information
Product ID:
5932
Production Date:
5/4/01
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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