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• Herbaceous production performance standard (weighted by percent of affected area) = 1053 Ib/ac. 90 percent of performance standard = 0.9 x 1053 = 948 Ib/ac ' Seneca II-W extended reference area values from data collected in 1999 ° Seneca II-WS extended reference area values from data collected in 1997 Woody Plant Density The woody plant density standard applicable to these lands as of 1999 is 2000 stems per acre. 1995 reclamation averaged 170 woody plant stems per acre, and 1997 reclamation averaged 275 woody plant stems per acre (Figure 3, Tables 3, 6 and 13) . These values are very typical of what has been observed over the long term in reclaimed areas at the nearby Seneca II Mine. In the 1995 reclaimed areas, the bulk of the total density was, as is typical, big sagebrush and mountain snowberry, but serviceberry comprised slightly over 10 percent of the total which is encouraging for the long-term. In the 1997 reclamation (some areas of which had been planted with tubling nursery stock), serviceberry was over 20 percent of the total density and Gambel's oak was over 10 percent of the total. Thus, although the absolute numbers per acre are not much different than previous experience in the area, and still are not particularly close to the 2000 stems/ac standard, the species composition of these areas includes species that can be considered important to the viability of these areas over the long-term. As the vegetation of the reclaimed areas responds to climate and management, among other environmental variables, it will be important that species representing principal components of the major vegetation types of the area (such as mountain brush) are present and available to become dominants again, should conditions support that development. Thus, perhaps more important than any overall woody plant • density standard is the presence of primary species as potential centers of propagation for future changes in species dominance. Species Diversity and Composition Species density data represent the total number of species present in randomly selected 100 square meter areas associated with the 50m cover sample transects. Species density data from the 1999 sampling are summarized in Table 14 and are graphically presented in Figure 4. In 1999, total species density among all reclaimed and reference areas sampled ranged between 26.5 and 32.0 species/ 100 mZ. The highest species densities observed were in the reclaimed areas. They exceeded the reference areas in total species density by from 0.7 to 5.5 species per 100 sq. m. Of course, the additional opportunities for the presence of introduced annual and biennial (orbs in these relatively young reclaimed areas accounted for some additional species. However, even in consideration of native species only, reclaimed areas, varying from 20.0 to 20.5 native species per 100 sq. m. compared favorably with reference areas which varied from 24.1 to 26.8 native species per 100 sq.m. Reclaimed areas tended to have more native perennial grass species and fewer native perennial forbs species than the reference areas. Relative cover by lifeform is summarized in Table 15 and graphically presented in Figure 5. Data on which this graph is based are presented in Tables 1, 4, 7, 9, and 11. As can be seen in Figure 5, the reclaimed areas are much more strongly dominated by herbaceous species, especially native perennial cool season grasses than the reference areas. In the Aspen, Mountain Brush, and Sagebrush/snowberry reference areas, the woody biomass supported by one or more centuries' cumulative growth allows only limited growth by herbaceous species. Although the herbaceous component of these native vegetation types is diverse, especially as pertains to perennial forbs, the physical dominance of the woody component leaves little room for • herbaceous species' growth.