2018-01-03_PERMIT FILE - C1981010A (12)

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• The following paragraphs briefly explain the method by which condition was deter- mined and the results obtained. It should be emphasized that a variety of meth- ods for a condition determination are presently used by range managers. The fol- lowing method was the most appropriate in terms of baseline data collected in 1979 and present land use. An alternative method is presented conceptually in Section 4.4. Neither method will necessarily be the only means by which condi- tion will be determined in the future. Condition will be evaluated every other year. Condition is not expected to change enough on a yearly basis to be detect- ed by available methods. In the summer of 1979, a preliminary survey of all vegetation within the mine plan area was made. The parameters measured during this survey included shrub density, aerial cover, and production of current annual growth (CAG). Condition was sampled by using five eight -meter transects in each vegetation type. A total of twenty points were sampled on each transect. If no basal hit was obtained at a sample point, the nearest individual to each point was recorded. • Condition was determined by listing individual species of grasses, grass -like plants, and shrubs. Forbs were not listed by species but were grouped together as "Forbs". The reasoning for such a classification is based on the premise that forbs are either poisonous or will be too rank by the time livestock use begins in late spring of each year. The condition of each vegetation type was based on the existing land use (grazing) and, type of livestock using the area (sheep). Such a method is patterned after a procedure recommended by Smith (1978). For example, plant species such as the wheatgrasses (Agropyron spp.) received a high (H) palatability rating while cheatgrass brome (Bromus tectorum) received a low (L) rating. Percent composition by cover was determined for each species. A11 species were then summed together based on high (H), moderate (M), or low (L) palatability ratings. Those plants in the group rated as "high" were classed as "decreasers", those in "moderate" as "increasers," and those in "low" as "invad- ers." The three individual totals (Table 2.3-22) were then used to find the approximate condition of the type (Stoddart et al, 1975)(Figure 2.3-1). For example, the big sagebrush -grass association was found to contain by composition • 40 percent decreasers, 31 percent increasers, and 29 percent invaders. Locating 2-115