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• The 1989 average vegetation cover reflected a reduction of 24 percentage points from the vegetation cover measured in 1987. The change in cover from 1987 to 1989 for the Sagebrush Reference Area was nearly the same as the reclaimed areas (approximately 25 percentage points). In 1990, the overall reclaimed area average rebounded by about 12 percent, while the Sagebrush Reference Area recovered by 9 percent. In 1991, the Sagebrush Reference Area cover increased by over 6 percent, while the reclaimed area average went up by about 5 percent. In 1992, the Sagebrush Reference Area declined by about 11 percent while the overall average dropped by about 8 percent. In 1993, the increase in cover in the reclaimed areas was accompanied by a slight increase in the Sagebrush Reference Area and a rather large jump in the Mountain Brush Reference Area. In 1994, the average reclaimed area cover declined by about 10 percent, while cover in the Sagebrush Reference Area declined by about 4 percent. In 1995, average reclaimed area cover increased by about 13 percent, while Sagebrush Reference Area cover rose by 8 percent. In 1996, cover in the Sagebrush Reference Area dropped by 5.6 percent while the overall average dropped by 10.7 percent. In 1997, cover in the Sagebrush Reference Area increased by 11 percent, while the reclaimed area number went up by 5.2 • percent. Over the period of record, including 1997, there has been a clear pattern in which cover in the reclaimed areas has varied similarly to cover in the Sagebrush Reference Area, which is more like the reclaimed areas in that it has greater herbaceous cover than does the Mountain Brush Reference Area. This, along with the prevalence of sagebrush and snowberry, suggests successional development of reclaimed areas toward the Sagebrush vegetation type. If reclaimed areas first achieve the greatest resemblance to the Sagebrush vegetation type, this is not to predict that they may not proceed through further succession toward composition more closely approximating Mountain Brush in time. On the other hand, through 1996, the heavy woody cover of the Mountain Brush Reference Area has shown a tendency to react with delay; reduction in cover percent during drought has been delayed, as has recovery following cessation of drought. The Mountain Brush Reference Area dropped only 9.7 percentage points from 1987 to 1989 (during the worst of the drought), but continued to drop another 2 percentage points in 1990 (as the drought abated). In 1991, the Mountain Brush Reference Area cover increased by nearly 8 percent, and in 1992 the total cover decreased by 13 percent. The 1992 decline relates partly to the fact that the boundaries of the • 13