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• compared to 1997 Mountain Brush and Sagebrush reference area values of 33.9 and 35.4 native species per 100 m2; 1996 values of 27.2 and 35.4 native species per 100 m2, 1995 values of 40.4 and 37.3 species/ 100 mZ; 1994 values of 31.3 and 28.3 species per 100 m2, respectively; 1993 values of 28.6 and 29.0 species per 100 m2, respectively; 1992 values of 33.9 and 24.6 species per 100 m2 ,respectively; 1991 values of 28.7 and 27.7 species per 100 mz ,respectively; and 1990 values of 22.9 and 25.9 species per 100 mZ ,respectively. Prior to 1995 it had been noted that the lowest reclaimed area values (usually the older areas) had steadily increased since 1990, suggesting that invasion of the reclaimed areas by native species was slowly but measurably observable. It had also been noted that the highest reclaimed area values (usually the younger reclaimed areas with more diverse seed mixes, more direct-haul topsoil areas, and more annual species, many of which are native) had climbed slowly since 1990 and that, even though they did not yet equal the levels of native species density found in the reference areas, there was a suggestion that plant succession was proceeding in these reclaimed area plant communities and that equality with native areas might eventually develop. In 1995, extraordinarily favorable growing conditions accompanied a rise • in native species density in reference areas but a decline in reclaimed area species density, probably due to the intense competitive effects of very vigorous growth of introduced grasses and alfalfa in the reclaimed areas. In reference areas, the dominant species do not respond so dramatically to improvements in growing conditions as do the introduced forage species in reclaimed areas. These introduced species have been bred for hundreds of years in the service of agriculture to respond with abundant herbaceous production it given sufficient moisture. In 1996 and 1997, the native species density of the reclaimed areas has risen again to approach the peak observed in 1994 sampling. 1997 sampling revealed 15.5 native species/ 100 mZ in the 1990 reclamation which, when last measured (1994), species density of native plants was 18.3 native species per 100 m2. This duplicates almost exactly the pattern observed in 1989 reclamation in 1993 and 1996, showing a slight decline in initial native species density values. Examination of Figure 4 reveals that, as observed in recent years, reclaimed areas approximate reference areas in the prominence of native perennial (orbs and grasses. However, reclaimed • areas also have more non-native species than the reference areas. 20