Sawtimber trees — Live trees of commercial species 

 containing at least one 12-foot saw log or two non- 

 contiguous 8-foot logs, and meeting regional speci- 

 fications for freedom from defect. Softwood trees 

 must be at least 9 inches in diameter and hard- 

 wood trees 1 1 inches in diameter at breast height. 



Sawtimber volume — Net volume of the saw log por- 

 tion of live sawtimber trees in board feet. 



Scenic rivers — Rivers or sections of rivers free of 

 impoundments, with shorelines or watersheds still 

 largely primitive and shorelines largely undevel- 

 oped, but accessible in places by roads. 



Seedlings — Established live trees of commercial spe- 

 cies less than 1.0 inch in diameter at breast height 

 and of good form and vigor. 



Seedling and sapling stands — Stands at least 10 per- 

 cent occupied with growing-stock trees of which 

 more than half of the stocking is saplings and/or 

 seedlings. 



Softwoods — Coniferous trees, usually evergreen, 

 having needles or scalelike leaves. 



Sound cull trees — (Rough trees) Live trees that do 

 not contain a saw log now or prospectively, pri- 

 marily because of roughness, poor form, or non- 

 commercial species. 



Special interest areas — Areas described in the Envi- 

 ronmental Policy Act of 1970 which include (1) 

 cultural areas — historic or prehistoric sites and 

 places of obvious future historical value, and (2) 

 natural areas — outstanding examples of the Na- 

 tion's geological and ecological features. 



Stand improvement — Measures such as thinning, 

 pruning, release cutting, girdling, weeding, or poi- 

 soning of unwanted trees aimed at improving 

 growing conditions for the remaining trees. 



Stand-size classes — A classification of forest land 

 based on the predominant size of timber present, 

 that is, sawtimber, poletimber, or seedlings and 

 saplings. 



State, county, and municipal land — Land owned by 

 States, counties, and local public agencies, or 

 lands leased by these governmental units for more 

 than 50 years. 



Stocking — The degree of occupancy of land by trees, 

 measured by basal area and/ or number of trees by 

 size and spacing, compared to a stocking standard, 

 i.e., the basal area and or number of trees required 

 to fully utilize the growth potential of the land. 



Threatened species — Any species of animal or plant 

 which is likely to become an endangered species 

 within the foreseeable future throughout all or a 

 portion of its range. 



Upper-stem portion — That part of the main stem or 

 fork of sawtimber trees above the saw log top to a 

 minimum top diameter of 4.0 inches outside bark 

 or to the point where the main stem or fork breaks 

 into limbs. 



Urban and other areas — Areas within the legal boun- 

 daries of cities and towns; suburban areas devel- 

 oped for residential, industrial, or recreational 

 purposes; school yards; cemeteries; roads; rail- 

 roads; airports; beaches; powerlines and other 

 rights-of-way; or other nonforest land not in- 

 cluded in any other specified land use class. 



Water resource region — The 21 major hydrologic 

 regions into which the United States is delineated. 



Wild rivers — Those rivers or sections of rivers free of 

 impoundments and generally inaccessible except 

 by trail, with watersheds or shorelines essentially 

 primitive (and waters unpolluted). 



Wilderness — An area of undeveloped Federal land 

 retaining its primeval character and influence, 

 without permanent improvements or human habi- 

 tation, which is protected and managed so as to 

 preserve its natural conditions and which (1) gen- 

 erally appears to have been affected primarily by 

 the forces of nature, with the imprint of man's 

 work substantially unnoticeable; (2) has outstand- 

 ing opportunities for solitude or a primitive and 

 unconfined type of recreation; (3) has at least 5,000 

 acres of land or is of sufficient size as to make 

 practicable its preservation and use in an unim- 

 paired condition; and (4) may also contain ecologi- 

 cal, geological, or other features of scientific, 

 educational, scenic, or historical value (from Wil- 

 derness Act 1964). 



Withdrawal use — Water that is taken from a source, 

 used, and then returned to a source for reuse. 



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