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VIII. DISCUSSION 1996 PRECIPITATION REGIlI4E Based on a comparison of precipitation records from the Paonia 1 SW station, the 1996 growing season was significantly drier than average. The growing season precipitation sum from 1995-1996 was 7.78 inches of precipitation, compared with the average of 11.08 inches. As this precipitation total is less than the dry year threshold value of 8.45 inches, vegetation sampling from the 1996 growing season should adequately represent vegetation cover, herbaceous production, and species composition from a dry precipitation year as envisioned in the historic record concept for the West Elk Mine. COMPARATIVE VEGETATION COMMUNITY SAMPLING AT THE WEST ELK MINE The historic record vegetation community closely resembles the vegetation community identified as dry meadow in the baseline vegetation survey conducted prior to permitting of the West Elk Mine. The dry meadow community has been extensively sampled during the last fifteen years. In doing so, a record of the characteristics of this community has been established. A comparison of the parameter values from the dry meadow vegetation community with those of the historic record vegetation community was undertaken to evaluate the nature of the historic record vegetation community relative to the dry meadow community. In 1982, both the dry meadow affected area vegetation community and dry meadow reference area vegetation communities were quantitatively sampled. In 1995, the dry meadow reference azea was sampled _. quantitatively (Savage and Savage, 1995). Values from those studies and parameter values from the 1996 historic record vegetation community sampling are provided in Tables 8 and 9. A comparison of total mean vegetation cover from the three sample yeazs and four sample vegetation communities (Table 8) illustrates the correlation between growing season precipitation and plant growth. In 1982, the growing season precipitation sum was 11.42 inches, not significantly different than the average of 11.47 inches. Dry meadow vegetation communities produced vegetation cover ranging from 40.97 to 46.85 percent. In 1995, where growing season precipitation was 24.06 percent greater than average, the dry meadow reference area vegetation community showed a corresponding increase in total vegetation cover of 39.16 percent. In 1996, when the growing season precipitation was 67.86 percent below average, the historic record vegetation community showed the lowest total vegetation cover of the sampling years reviewed. Herbaceous production from the three sampling yeazs and four vegetation sample locations also appeared correlated to growing season precipitation, though not as -16-