Acres of Pastureland, 1997
Description
This dot density map shows the distribution of
pastureland. Dots are aggregated by and placed
randomly within 8-digit hydrologic units. Each
green dot represents 25,000 acres of
pastureland. Areas with 95% or more Federal area
are shaded gray. There are 120 million acres of
pastureland in the U.S.
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.
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
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]
Land cover/use:
A term that includes categories of land cover
and categories of land use. Land cover is the
vegetation or other kind of material that covers
the land surface. Land use is the purpose of
human activity on the land; it is usually but
not always related to the land cover. The NRI
uses the term (land cover/use) to identify the
categories that account for all the surface area
in the United States [BS-1982; NRI-97]
Pastureland and Native Pasture:
A Land Cover/Use category of land managed
primarily for the production of introduced or
native forage plants for livestock grazing.
Pastureland 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, includes land that has a
vegetative cover of grasses, legumes, and/or
forbs, regardless of whether or not it is being
grazed by livestock.) [NRI-97]
Product Information
Product ID:
5119
Production Date:
1/25/01
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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