Acres of Non-Federal Grazed Forest Land, 1987
Description
This dot density map shows the total acres of
1987 Non-Federal grazed forest land. Dots are
aggregated by and placed randomly within 8-digit
hydrologic units. Each green dot represents
10,000 acres of grazed forest land. Areas with
95% or more Federal area are shaded gray. There
were 64.2 million acres of non-Federal grazed
forest land in the U.S. in 1987. Grazed forest
is a sub-category of Forest Land.
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
Forest land:
A Land Cover/Use that is at least 10 percent
stocked by single stemmed forest trees of any
size which will be at least 4 meters (13 feet)
tall at maturity. When viewed vertically,
canopy cover is 25 percent or greater. Also
included are areas bearing evidence of natural
regeneration of tree cover (cutover forest or
abandoned farmland) and not currently developed
for nonforest use. For classification as forest
land, an area must be at least one acre and 100
feet wide. [NRI-97]
Forest land, grazed:
Forest land that is being grazed by livestock
and managed using range management principles
and practices adapted to the forest ecosystem.
[NCPM].
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.
Product Information
Product ID:
6038
Production Date:
5/23/01
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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