Average
Annual Mortality of Softwood Growing-Stock Trees on Timberland, 2002
Description
This map shows the spatial distribution of the average annual mortality
of softwood growing-stock trees on timberland by county. Nationwide,
the total is roughly 3.5 billion cubic feet per year.
Use this map only to identify broad spatial trends. At the
time of
assessment, data were not available for interior Alaska,
the Pacific Basin, Puerto
Rico, U.S. Virgin Islands, and a small number of counties
in the lower 48 states.
Sources:
USDA Forest Service, 2002 RPA data, available at: http://fia.fs.fed.us/tools-data/tools/.
Distributor:
USDA Forest Service, Forest Inventory and Analysis.
Layers:
USDA Forest Service, 2002 RPA data and the National Atlas
of the United States.
Definitions:
Growing stock trees - Live trees of commercial species which meet
specified standards of quality and vigor. Trees classified as growing
stock are commercial species of good form that are at least 5.0
inches diameter breast height (dbh) (4.5 feet). Trees not classified
as growing stock are classified as cull trees.
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