|
| |
Percent of Non-Federal Area in Rangeland, 1992
Description
This map shows the spatial distribution of the
nation's non-Federal rangeland in 1992 as a
percentage of the total non-Federal land area
for each 8-digit hydrologic unit. Nationwide
407,379,700 acres of non-Federal area are
rangeland. Areas with 95% or more federal area
are shaded gray. This map replaces map #2096.
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:
States, Rivers
Definitions
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]
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.
Rangeland:
A Land cover/use category on which the climax or
potential plant cover is composed principally of
native grasses, grasslike plants, forbs or
shrubs suitable for grazing and browsing, and
introduced forage species that are managed like
rangeland. This would include areas where
introduced hardy and persistent grasses, such as
crested wheatgrass, are planted and such
practices as deferred grazing, burning,
chaining, and rotational grazing are used, with
little or no chemicals or fertilizer being
applied. Grasslands, savannas,
many wetlands, some deserts, and tundra are
considered to be rangeland. Certain communities
of low forbs and shrubs, such as mesquite,
chaparral, mountain shrub, and pinyon-juniper,
are also included as rangeland.
[NRI-97]
Product Information
Product ID:
5022
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.
| | |