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• .Sagebrush Extended Reference Area (Photographs 17 through 20) Cover (Table 11) The native shrub lifeform category was the dominant in this area and provided 57.2 percent of total vegetation cover. Big sagebrush and mountain snowberry each contributed more than two- fifths of this total. Saskatoon serviceberry and Douglas rabbitbrush were also important members of this community. Rubber rabbitbrush (Chrysofhamnus nauseosus), bitterbrush, and Gambel's oak made relatively minor contributions. Native perennial cool season grasses accounted for 28.3 percent of total vegetation cover. Agassiz bluegrass comprised one-half of this total. Slender wheatgrass was also a significant contributor. The balance was comprised by fourteen other species. Native perennial forbs contributed 11.4 percent of total vegetation cover. Western yarrow accounted for approximately one-fifth of this total. Arrowleaf balsamroot (Balsamorhiza sagittata), one-flower woodsunflower, silver lupine, and chokecherry lupine were also important contributors. Twelve other species made relatively minor contributions. Introduced annual and biennial forbs accounted for 1.5 percent of total vegetation cover. Hound's tongue, twolobe speedwell, and salsify each contributed to this total. Introduced annual grasses contributed 0.6 percent of total vegetation cover. Cheatgrass and Japanese brome contributed equally to this total. Moss averaged 0.6 percent and Douglas knotweed, a native annual forb, averaged 0.3 percent of total vegetation cover. Total vegetation cover was 66.4 percent. Standing dead, litter, bare soil, and rock cover values were 3.2, 22.4, 7.8, and 0.2 percent respectively. Species density averaged 26.5 species per 100 sq. m. Herbaceous Production (Table 12) • Total herbaceous production was 1224 pounds per acre. No alfalfa was observed in this reference area. Discussion Climatic Conditions Late 1998/ early1999 precipitation was up and down, with August, November, December, February and March all below average, and the other months above average (Figures 6a and 6b). The total for the year ending in July 1999 (Figures 7a and 7b) was below average in distinct contrast to the past four years (1995 to 1998). It was comparable to, but was not as severe as the drought years in the period from 1988 to 1990 as well as 1993 and 1994. When viewed over shorter terms (Figures Sa, 8b, 9a and 9b), 1999 is in the middle of the range of variation but in the upper echelon of individual years since the distribution of values for four and six month cumulative totals is distinctly skewed to the dry side (at least in July). With respect to warmth of• the growing season, as reflected in the cumulative degree-days shown in Figure 10, 1999 was very near the long-term average. This contrasts with the last tour years that had been below average in warmth. Of particular interest in the pattern of vegetational growth shown in 1999 was the very dry August in 1998 and the very wet April, May, and July of 1999 (see below). Cover 1999 efforts were directed toward monitoring of the revegetation in selected areas at the Seneca II-W Mine. Samples were taken in numbers that experience in the area had showrrwould usually result in a data set with variance characteristics that approximate "sample adequacy." Inasmuch as formal bond release was not being sought in 1999, such data sets would be sufficient to • compare reclaimed area cover values to performance standards.