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• reference area as sampled for 1992 had been adjusted to reflect the originally identified <br />reference area limits more correctly, and included less of the very heavy oak and serviceberry <br />stands on the steep east-facing slopes; this is responsible for at least some of the decline in <br />cover since experience has shown the dense overhead canopy of these species generally <br />corresponds to higher total plant cover than any other type of vegetation in the area. In 1993, <br />with the same sample area boundaries used in 1992, the total cover increased by 7.3 percent. In <br />1994, the Mountain Brush Reference Area was subject not only to the severe drought conditions, <br />but was inadvertently affected by herbicide drift as a local rancher attempted to remove shrub <br />cover from nearby grazing areas. Between the drought and herbicide accident, the result was a <br />decrease in cover to 66.8 percent; the previous lowest observed cover in the area since 1987 was <br />74.9 percent in 1992. What part of this decrease was attributable to drought and what part was <br />due to herbicide effects is not known. In the only reclaimed area measured every year (Wadge <br />Pasture), there was a 16.5 percent drop in cover in 1994, suggesting that the drought effect may <br />be substantial. Mountain Brush Reference cover in 1995 recovered to 79.0 percent, well within <br />the previously observed range of values. The delayed reaction of the Mountain Brush Reference <br />Area was again shown in 1996 as cover rose following the very favorable 1995 season while all <br />• other areas declined. In 1997, the Mountain Brush Reference Area rose by an additional 3.8 <br />percent cover. <br />Herbaceous Production <br />Only the herbaceous component was sampled for annual production in both the reclaimed and <br />reference areas. Because the reference areas are both dominated by woody plants, the <br />herbaceous component of production is small and is greatly exceeded by the production of the <br />reclaimed areas where woody plants comprise only a small amount of total vegetation <br />composition (Figures 2 and 5). Whether or not the large annual herbaceous production of the <br />reclaimed areas equals or exceeds the total (woody plus herbaceous) annual production of the <br />reference areas is unknown. <br />Over the period of 1987 to 1997, the levels of herbaceous production observed have varied as <br />follows: <br />• <br />14 <br />