Acres of Non-Federal Forest Land, 1987
This dot density map shows the total number of 1987 forest land acres. Dots are aggregated by and placed randomly within 8-digit hydrologic units. Each green dot represents 25,000 acres of non-Federal forest land. Areas with 95% or more Federal area are shaded gray. There were 405.3 million acres of non-Federal forest land in the U.S. in 1987.
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.
Source: National Resources Inventory, 1997
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.
Aggregate Layer: Cross of State with 8 Digit Hydrologic Units and Federal Land
Other Layers Displayed: States, Rivers
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]
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]
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]
Product ID: 5980
Production Date: 5/7/01
Product Type: Map
For additional information contact the Resources Inventory and Assessment Division. Please include the Product ID you are inquiring about. email@example.com 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.