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u <br />Likewise, in the only other area with greater than 300 shrub stems per acre, the 1986 Wadge i <br />area, bare soil is much more prevalent than average (approximately 10 to 15 percent bare <br />soil). <br />Review of 1985, 1987,1988,1989, and 1990 sampling data for the Seneca Mine shows the <br />following documented average shrub density by year: <br />Samolino Year Stems /acre <br />1985 378 <br />1987 300 <br />1988 314 <br />1989 288 <br />1990 281 <br />CI <br /> <br />Although these data were collected from different areas during these years, and the numbers <br />are thus not strictly comparable, the trend of decreasing, or at least not increasing, shrub 5 <br />density is probably real and may be related to competition from the heavy herbaceous growth <br />that comprises the high production discussed above. It may also be related to effects of the <br />ongoing drought. In the Wadge Pasture, shrub densities in 1988, 1989, and 1990 were 320, <br />476, and 408 stems per acre, respectively. Thus, the apparent substantial increase in density <br />in 1989 was partially lost by 1990. In 1989, slightly over 50 percent of the shrubs ', <br />encountered in the Wadge Pasture sampling were classified as seedlings. It is possible that a <br />large portion of these seedlings died by 1990, accounting for most of the losses. There were <br />virtually no seedlings found in 1990. ~ <br />Species Diversity and Composition <br />Species density reflects the total number of species present (richness) in 100 square meters <br />adjacent to cover sample transects. Species density data are graphically presented in Figure 4. <br />As can be seen in Figure 4, as well as the data in Table 39, the total species density of the <br />reference areas is in the range of 25 to 27 species/ 100 sq.m. This level is equaled or <br />exceeded in 6 of the 10 reclaimed areas examined in 1990. Whereas, in previous years, young <br />reclamation with abundant weedy species often has exceeded the reference area species <br />density, in 1990, the 1983 Wolf Creek, the 1986 Wadge Spring, and the 1986 Wadge areas <br />all equal or substantially exceed the reference area levels. In terms of native species density, <br />the values varied from 9.5 to 18.9 species per 100 m'in the recalimed areas, compared to <br />22.9 and 25.9 species per 100 m' in the Mountain Brush and Sagebrush Reference Areas, <br />respectively. The highest native species density in the reclaimed areas was 18.9 in the 1983 <br />17 <br />