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1 1 1 1 1 Big Sagebrush Reference Area. The big sagebrush reference area (Photo 4) is located on a gentle north-facing slope adjacent to the north side of the grassland reference area (Map 1). The major species in this reference area include big sagebrush, Idaho fescue (Festuca idahoensis), aloes-growing species of rabbitbrush (Chrysotlwmnus aaseyi), prairie Junegrass and thickspike wheatgrass. These five species accounted for 92.8 percent of the cover by all species (Table 8). The remaining 7.2 percent of the cover was distributed among 27 other species. Big sagebrush accounted for 46.8 percent of the cover by all species. Mean total vegetation cover was 45.4 percent, cover by litter and rock combined was 46.7 percent, bare soil cover was 7.9 percent and total ground cover was 92.1 percent. Species diversity had a mean value of 14,7 species per transect. Mean total production was 46.4 g/m~ with 99 percent of the total attributable to cool season perennial grasses (Table 9). Major species included Idaho fescue, prairie Junegrass and thickspike wheatgrass. Comparison Between 1997 and 1998 The following table summarizes the 1997 and 1998 results for total vegetation cover, biomass production and woody plant density for the two reclaimed areas and for the reference areas. The results from the two years of sampling suggest that differences between the two years are minimal, and that the differences most likely relate to sampling variance rather than to actual differences. Mean values for most of the year- to-year comparisons are no greater than 10 percent, which is within the margin of error expected from the sampling programs. Additionally, the noted differences were not always consistent, that is neither year had consistently higher or lower values. Mean total vegetation cover was higher in 1997 for the 1984 reclaimed area and the grassland reference area. For the 1988 reclaimed area and the shrubland reference area, the 1998 mean values were higher. Mean production was higher in 1997 for the 1984 reclaimed area, the 1988 reclaimed area and the grassland reference area. For the shrubland reference area, mean production was higher in 1998. Total Biomass Woody Plant Density Vegetation Production Area (Individuals per acre) Cover % mz 1997 1998 1997 1998 1997 1998 1984 Reclaimed Area 32.6 31.1 23.4 20.8 13,933 13,636 1988 Reclaimed Area 30.6 33.2 84.6 70.1 3,026 2,774 Grassland Reference 28 4 75.6 36.0 30.4 Area shrubland Reference 42 6 45.4 45.2 46.4 Area -4- 1