Glossary 



Aggregated subarea — Subdelineations of water re- 

 source regions — also based upon hydrologic 

 boundaries. 



Animal unit months (AUM'S) — Amount of grazing 

 required by a 1,000 pound cow for 1 month. 



Biological potential — The amount of living matter 

 potentially producible by the unit being discussed 

 without fertilization or irrigation. 



Bureau of Land Management land — Federal lands 

 administered by the Bureau of Land Management, 

 U.S. Department of the Interior. 



Commercial forest land — See commercial timber- 

 land. 



Commercial species — Tree species suitable for indus- 

 trial wood products. 



Commercial timberland — Forest land which is pro- 

 ducing or is capable of producing crops of indus- 

 trial wood and not withdrawn from timber utiliza- 

 tion by statute or administrative regulation. (Note: 

 Areas qualifying as commercial timberland have 

 the capability of producing in excess of 20 cubic 

 feet per acre per year of industrial wood in natural 

 stands. Currently, inaccessible and inoperable 

 areas are included.) 



Consumptive water use — Portion of water with- 

 drawn that is consumed through evaporation, 

 transpiration, or discharge into irretrievable 

 locations. 



Cord — A pile of stacked wood containing 128 cubic 

 feet within its outside surfaces. The standard 

 dimensions are 4 by 4 by 8 feet. 



Cropland — Land under cultivation within the past 

 24 months, including cropland harvested, crop 

 failures, cultivated summer fallow, idle cropland 

 used only for pasture, orchards and land in soil 

 improving crops, but excluding land cultivated in 

 developing improved pasture. 



Cull trees — Live trees of sawtimber and poletimber 

 size that are unmerchantable for saw logs now or 

 prospectively because of roughness, rot, or species 

 (also see rotten cull trees and rough trees). 



Deferred forest land — National Forest lands that 

 meet productivity standards for commercial forest, 

 but are under study for possible inclusion in the 

 Wilderness System. 



Depletion — The utilization of a natural renewable 

 resource at a rate greater than the rate of 

 replenishment. 



Developed (or concentrated) recreation — Outdoor 

 recreation requiring significant capital investment 

 in facilities to handle a concentration of visitors on 

 a relatively small area. 



Diameter classes — A classification of trees based on 

 diameter of outside bark measured at breast height 



(4'/2 feet above the ground). D.b.h. is the common 

 abbreviation for "diameter at breast height." 

 When using 2-inch diameter classes the 6-inch 

 class, for example, includes trees 5.0 through 6.9 

 inches d.b.h. inclusive. 



Dispersed recreation — Outdoor recreation in which 

 visitors are diffused over relatively large areas. 

 Where facilities or developments are provided, 

 they are more for access and protection of the 

 environment than for the comfort or convenience 

 of the people. 



Domestic water use — Water used for drinking, sani- 

 tation, street flushing, fire protection, and lawn 

 and garden irrigation. 



Ecosystem — A complete, interacting system of or- 

 ganisms considered together with their environ- 

 ment, e.g., a marsh, a watershed, a lake, etc. 



Endangered species — Any species of animal or plant 

 which is in danger of extinction throughout all or a 

 significant portion of its range. 



Establishment — An economic unit, generally at a 

 single physical location, where business is con- 

 ducted or where services or industrial operations 

 are performed. 



Farmer and other private — All private ownerships 

 except industry. 



Farmer-owned lands — Lands owned by a person 

 who operates a farm, either doing the work himself 

 or directly supervising the work. 



Forest industry lands — Lands owned by companies 

 or individuals operating wood-using plants. 



Forest land — Land at least 10 percent stocked by 

 forest trees of any size, including land that for- 

 merly had such tree cover and that will be natu- 

 rally or artificially regenerated. (Also see Com- 

 mercial forest land. Productive-reserved forest 

 land, and Other forest land.) Forest land includes 

 transition zones, such as areas between heavily 

 forested and non-forested lands that are at least 10 

 percent stocked with forest trees, and forest areas 

 adjacent to urban and built-up lands. Also in- 

 cluded are pinyon-juniper and chaparral areas in 

 the West, and afforested areas. The minimum area 

 for classification of forest land is 1 acre. Roadside, 

 streamside, and shelterbelt strips of timber must 

 have a crown width at least 120 feet wide to qualify 

 as forest land. Unimproved roads and trails, 

 streams, and clearings in forest areas are classified 

 as forest if less than 120 feet in width. 



Forest site productivity class — A classification of 

 forest land in terms of potential cubic-foot volume 

 growth per acre at culmination of mean annual 

 increment in fully stocked natural stands. 



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