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L <br />' Data were recorded as "hits" on vegetation (recorded by species), litter, bare soil or rock. The data <br />were surtunarized by computing mean cover, relative cover (percent of total vegetation cover <br />attributed to each species), frequency (the number of transects of occurrence by a species divided <br />by the total number of transacts), and relative frequency (percent of the total number of transacts of <br />occurrence attributed to each species. Relative cover and relative frequency were summed to <br />' obtain an importance value on which all species were serially ranked. <br />Species Diversity. Lrformation oa species diversity was obtained by keeping track of all <br />' the observed species in each of the sampled areas. The mean number of species per traasect was <br />also determined. Species that were observed in each of the areas but were not encountered as hits <br />on the transact lines, appear in the cover data tables as species with less than one percent mean <br />' cover and zero percent frequency. <br />Biomass Production. Biomass production data were obtained using a harvest method. All <br />' of the current years growth included within a single 1.0 square meter quadrat was clipped at each <br />of the random biomass sampling sites. Clipped samples were sorted based on species for grasses <br />and semi-shrubs. Some forts were clipped on the basis of species and others were grouped into <br />' samples based on life forms. Shrubs, cushion plants and cacti were not clipped. Clipped samples <br />were placed in paper bags, then returned to the laboratory, ovendried and weighed. Sample <br />adequacy evaluations were conducted in the Seld on the basis of fresh weights. <br />Shrub Density. Shrub density data were collected using a line transact approach. All <br />shrubs oceurring within one meter on either side of the 25 meter transact line (used for collecting <br />' cover data) were counted on the basis of species. Data were collected in both reclaimed areas as <br />well as in the reference areas. Sample adequacy was obtained for each of the reclaimed areas. The <br />evaluation of adequate shrub density on the reclaimed aeeas was made on the basis of an <br />' established standard rather on the basis of comparison with the reference areas. For this reason, <br />sample adequacy was not obtained for shrub density in the reference areas. <br />RESULTS <br />1984 Reclaimed Area. The 1984 reclaimed area (Photo 1) is located in the northeast <br />' comer of the property and covers approximately 29 acres (Map 1). The major species in this area <br />is big sagebrush (Artemtsia tridentate), which had a mean cover of 20.4 percent in 1997. This <br />species accounted for 62.6 percent of the cover by all species (Table 2). Thickspike wheatgrass <br />' (Agropyron dasystachyumJ was the most prevalent herbaceous and bad a mean cover of 6.2 <br />percent, which was 19 percent of the total by all species. The remaining 18 percent of the cover <br />was distributed among 24 other species (Table 2). Mean total vegetation cover was 32.6 percent, <br />cover by litter and rock combined was 39.5 percent, bare soil cover was 27.8 percent and total <br />' ground cover was 72.2 percent. Species diversity, as measured by the mean number of species per <br />transact, was 4.27. <br />Mean total production (excluding shrubs) was 23.4 g/m2 with thickspike wheatgrass <br />' accounting for 46 percent of the total. Green ncedlegrass (Stipa viridula) accounted for 22.8 <br />percent of the total, and Russian wildrye (Elymus junceus) accounted for 19.5 percent of the total. <br />The remaining 12 percent of the biomass was distributed among 13 other species or species groups <br />' (Table 3). <br />Individuals of big sagebrush are abundant in this area. Mean density for this species was <br />13,911 individuals per acre, which was 99.8 percent of all counted shrubs (Table 10). Two other <br />' shrub species were encountered. <br />' 2 <br />