grass, or western wheatgrass and needlegrass. 

 Occasional shrubs include juniper, silver sage- 

 brush, silver buffaloberry, skunkbush sumac, 

 rabbitbrush, and mesquite. 

 Prairie — Rangeland characterized by the tall 

 grasses, bluestems constituting about 70 percent 

 of the vegetation. Large numbers of flowering 

 forbs are present but are usually overshadowed 

 by the grasses. Woody vegetation is rare. 

 Desert grasslands — Rangeland with grasses pre- 

 dominant on plateaus at intermediate eleva- 

 tions, and shrubs predominate at higher and 

 lower elevations. Important grasses are galleta, 

 black grama, tobasa, and three-awn. 

 Wet grasslands — Rangeland characterized by 

 vegetation forming a medium-tall to very tall, 

 usually dense grassland, consisting of cord- 

 grasses, wiregrass, or sawgrass. Includes 

 marshes dominated by tule, bulrush, cattail, or 

 soft flag. There may be scattered palms, shrubs, 

 and low to medium-tall broadleaved evergreen 

 trees and shrubs. 

 Annual grasslands — Rangeland characterized by 

 annual grasses, such as wild oats, brome, wild 

 barley, and fescue. Forbs are numerous and 

 filaree is the most important. 

 Alpine — Rangelands dominated by grasses, wood- 

 rush, and sedges of rather low stature, but with 

 a large number of associated forbs. Common 

 grasses are bentgrass, hairgrass, mountain tim- 

 othy, bluegrasses, and spike tristetum. Dwarf 

 willow occurs, in some places, on the moist soils 

 of protected slopes and valleys. 

 Recreation visitor day — Twelve visitor hours, which 

 may be aggregated continuously, intermittently, or 

 simultaneously by one or more persons. 

 Removals — The net volume of growing stock or saw- 

 timber trees removed from the inventory by har- 

 vesting; cultural operations, such as timber stand 

 improvement; land clearing; or changes in land 

 use. 

 Residues 



Coarse residues — Plant residues suitable for chip- 

 ping, such as slabs, edgings, and ends. 

 Fine residues — Plant residues not suitable for 

 chipping such as sawdust, shavings, and veneer 

 clippings. 

 Plant residues — Wood materials from primary 

 manufacturing plants that are not used for any 

 product. 

 Logging residues — The unused portions of saw- 

 timber and poletimber trees cut or killed by 

 logging. 



Urban residues — Wood materials from urban 

 areas, such as newspapers, lumber, and ply- 

 wood from building demolition, and used 

 packaging and shipping wood materials. 



Rotten cull trees — Live trees of commercial species 

 that do not contain a saw log now or prospec- 

 tively, primarily because of rot (e.g., when rot 

 accounts for more than 50 percent of the total cull 

 volume.) 



Rough trees — (a) Live trees of commercial species 

 that do not contain at least one 12-foot saw log, or 

 two noncontiguous saw logs, each 8 feet or longer, 

 now or prospectively, primarly because of rough- 

 ness, poor form, splits, and cracks, and with less 

 than one-third of the gross tree volume in sound 

 material; and (b) all Hve trees of noncommercial 

 species. 



Roundwood equivalent — The volume of logs or 

 other round products required to produce the 

 lumber, plywood, woodpulp, paper, or other sim- 

 ilar products. 



Roundwood logs — Logs, bolts, or other round sec- 

 tions cut from trees. 



Salvable dead trees — Standing or down dead trees 

 that are considered currently or potentially mer- 

 chantable by regional standards. 



Sampling error — An expression of the degree of con- 

 fidence that can be placed on an estimated total or 

 average obtained by statistical sampling methods. 

 Sampling errors do not include technique errors 

 that could occur in photo classification of areas, 

 measurement of volume, or compilation of data. 



Saplings — Live trees of commercial species 1.0 inch 

 to 5.0 inches in diameter at breast height and of 

 good form and vigor. 



Saw log — A log meeting minimum standards of 

 diameter, length, and defect, including logs at least 

 8 feet long, sound and straight, and with a min- 

 imum diameter inside bark for softwoods of 6 

 inches (8 inches for hardwoods) or other combina- 

 tions of size and defect specified by regional 

 standards. 



Saw log portion — That part of the bole of sawtimber 

 trees between the stump and the saw log top. 



Saw log top — The point on the bole of sawtimber 

 trees above which a saw log cannot be produced. 

 The minimum saw log top is 7.0 inches d.o.b. for 

 softwoods, and 9.0 inches d.o.b. for hardwoods. 



Sawtimber stands — Stands at least 10 percent occu- 

 pied with growing-stock trees, with half or more of 

 total stocking in sawtimber or poletimber trees, 

 and with sawtimber stocking at least equal to pole- 

 timber stocking. 



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