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V. DISCUSSION 1997 PRECIPITATION REGIME Precipitation from October 1996 through May 1997 yielded total precipitation in the amount of 11.15 inches based on National Weather Service records from the Paonia I SW station. The CDMG calculated "pre-growing season" precipitation mean for the purposes of the historic record is 11.08 inches. For sampling purposes, "normal" years were defined as those years with a "pre-growing season" precipitarion total (as recorded by the National Weather Service or their designee) greater than 8.45 inches and less than 13.71 inches. $ased on this definition, the "pre-growing season" precipitation for 1997 was determined to fall within the "normal" range. Vegetation parameter values from the 1997 growing season should represent vegetation cover, herbaceous production, and species composition from a normal precipitation year as envisioned in the historic record concept for the West Elk Mine. 1997 VEGETATION SAMPLING Vegetation sampling at the historic record study area in 1997 represented the second consecutive year of data collection at the historic record vegetation community. As noted, the total precipitation received prior to the 1997 growing season was 3.37 inches more than in 1996. As a result of the increased precipitation, several notable observations were made in 1997. A 74.5 percent increase in total vegetation cover was noted in the historic record _ vegetation community from 1996 to 1997. The dominant plant species remained Bromus inermis followed by Poa pratensis. Bromus inermis showed a 135.1 percent increase in total cover from 1996 to 1997. Poa pratensis total cover decreased from 1996 to 1997 by 8.49 percent. Conwlw/us arvensis revealed the largest increase in total cover of all species from 1996 to 1997 with a 244.6 percent increase. A sub- dominant species in 1996, Agropyron intermedium showed the largest decrease in total cover from 1996 to 1997, with a 78.1 percent drop in total cover. Interestingly, the dominant plant species did not show increases in relative cover equivalent in value to that of the vegetation community as a whole. Bromus inermis showed an increase of 28.56 percent relative cover from 1996 to 1997, while Poa pratensis showed a 47.23 percent decrease in relative cover from 1996 to 1997. Agropyron intermedium, asub-dominant in 1996, fell from 22.63 percent relative cover in 1996 to 2.41 percent relative cover in 1997. Conw/wlus arvensis increased in relative cover from 5.50 percent to 11.22 percent in one year. Nine species which were not represented in cover sampling in 1996 appeared in 1997. _¢