Land use influence zones 



Zones delineated around areas or regions where it is likely that other 

 nontimber uses or environmental constraints would have an impact on 

 availability of timber. 



Mean annual increment 



A measure of the volume of wood, in cubic feet, produced on 1 acre 

 during 1 year. Forest Survey minimum standard for commercial forest 

 land is the ability to produce 20 ft^ /acre/year. 



Miscellaneous federal 



Federal lands other than national forest lands, lands administered by the 

 USDI Bureau of Land Management, or Indian lands. 



Mortality 



Number of sound-wood volume of growing stock trees dying from natural 

 causes during a specified period. 



Mortality tree 



A tree of commercial species, 5.0 inches d.b.h., or larger standing or 

 down, that has died within the past 5 years and was not a cull tree at 

 the time of death. 



National forest land 



Federal lands which have been designated by executive order or statute 

 as national forests or purchase units and other lands under the admini- 

 stration of the USD A Forest Service, including experimental areas. 



Net annual growth 



The increase in net volume of a specified size class for a specific year. 

 (Note: Components of net annual growth include the increment in net 

 volume of trees at the beginning of the specific year surviving to its 

 end, plus net volume of trees reaching the size class during the year, 

 minus the net volume of trees that died during the year, minus the net 

 volume of trees that became rough or rotten trees during the year) . 

 Net growth figures in this in this publication when expressed as 

 ft^ /acre/year of growing stock are for all live growing stock trees 5.0 

 inches d.b.h. and larger. 



Net volume 



The gross volume of a tree less deductions for rot, sweep, or other de- 

 fect affecting use for wood products. 



Noncommercial forest land 



Forest land incapable of producing 20 cubic feet per acre of industrial 

 wood under management, because of adverse site conditions, includes on- 

 ly nonreserved forest land. 



Noncommercial species 



Tree species of typically small size, poor form, or inferior quality 

 which normally do not develop into trees suitable for industrial wood 

 products. 



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