Acres of Prime Farmland Used as Cropland, 1997
Description
This dot density map shows the location of prime
farmland that is used as cropland (cultivated
and non-cultivated). Each dot represents 25,000
acres. Dots are aggregated by and placed
randomly within 8-digit hydrologic units. Areas
with 95% or more Federal area are shaded gray.
There are 212 million acres of prime farmland
used as cropland.
Cautions for this Product:
This map does not include prime farmland that is
not used as cropland or cropland that is not
located on prime farmland. This map may not be
used for site-specific information. 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:
Cross of State with 8 Digit Hydrologic Units and
Federal Land
Other Layers Displayed:
States, Rivers
Definitions
Cropland:
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]
Cultivated Cropland:
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.
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]
Hayland:
A sub-category of Cropland managed for the
production of forage crops that are machine
harvested. These crops may be grasses, legumes
or a combination. Hayland also includes land in
set-aside or other short-term agricultural
programs. [NRI-97]
Horticultural cropland:
A sub-category of Cropland used for growing
fruit, nut, berry, vineyard and other bush fruit
and similar crops. Nurseries and other
ornamental plantings are included. [NRI-97]
Non-cultivated cropland:
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.
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:
4966
Production Date:
12/13/00
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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