2011-03-16_GENERAL DOCUMENTS - C1980007

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remaining species have shown an increase in individuals over time. This is not unexpected, as these species are more adapted to an open environment, in association with graminoid species. Artemesia tridentata, Chrysothamnus nauseous, and Guterrezia sarothrae are also opportunistic pioneer species in successionally young vegetation communities. 5.3.4 HRSA Species Composition: 1996-2010 Total species numbers correlated with "pre-growing season" precipitation in a directly proportional relationship since sampling at the historic record vegetation community began. Species number increased from the dry 1996 to the mesic 1997 and decreased from the more mesic 1997 to the drier 1998 (Table 7.). In 2010, species numbers were above average when compared to historic record vegetation community sampling in the 1990's, and higher than a direct correlation with pre-growing season precipitation would suggest. One new species, Balsamorhiza sagitta (balsamroot) was encountered since the last historic record vegetation community sampling in 1998. This species is a native cool season perennial forb found commonly in adjacent oakbrush and mountain shrub vegetation communities. The species numbers from the historic record vegetation community sampling indicate that the composition of the community is very stable, as there have been no significant increases or decreases in species numbers over the years, nor have there been significant changes in the representation of the dominant species or physiognomy of the community since sampling began in 1996. 5.4 COMPARATIVE VEGETATION COMMUNITY SAMPLING AT THE WEST ELK MINE The historic record vegetation community was selected because of a close resemblance (location, elevation, aspect, soils, and vegetation community structure) to the dry meadow herbaceous vegetation community present within the West Elk Mine permit area (Savage and Savage, 1996, 1997, 1998). The dry meadow community was sampled in 1982 and the dry meadow reference area was sampled in 1982 and 1995 (MCC, 1997, Savage and Savage, 1995). While the dry meadow community (either affected area or reference area) is no longer being quantitatively sampled, it is productive to compare observations made at the historic record vegetation community to those from the dry meadow community within Sylvester Gulch. Tables 7 and 8 provide comparisons of the sampled parameters for the dry meadow community, dry meadow reference area, and the historic record vegetation community from the years 1982 through 2010. Relative cover in the dry meadow affected area, dry meadow reference area, and historic record vegetation community during the sample years 1982, 1995, 1996, 1997, 1998, and 2010 illustrates dominance by one cool season grass species in each of the communities (Table 8). In the 1982 dry meadow community, the species was Agropyron smithii. In the dry meadow reference area and the historic record vegetation community, the species Mountain Coal Company, LLC Page 10 Historic Record Study Area Vegetation Sampling Report: 2010