2011-10-03_REVISION - C1980007 (2)

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mean total vegetation cover mean (57.53 %) for the 2011 reclaimed area sampling units significantly exceeded the final total vegetation cover revegetation success value of 53.04 percent; therefore no statistical analysis was necessary. 2.5 SPECIES IDENTIFICATION AND VERIFICATION Species identification was accomplished in the field through the use of plant identification keys (Harrington, 1954, Weber, 1990; Whitson, 1987; Zimdahl, 1990, Stubbendieck, et al, 1995). In cases where plant identification was inconclusive in the field, voucher specimens were pressed for lab identification. 3.0 RESULTS 3.1 QUANTITATIVE EVALUATION: RECLAIMED AREAS The reclaimed areas sampled encompass just over 67.6 acres in 61 identified distinct parcels within eleven locales within the West Elk Mine permit area. The reclaimed areas range from 0.1 to 14.0 acres in size and ranged in age from three (3) to fifteen (15) years. The location, size, and age of the reclamation sites are presented above in the West Elk Mine 2011 Bond Release Sampling Phase II Eligible Areas table. Specific vegetation information for the reclaimed areas is contained in Tables 1. and 2. 3.1.1 VEGETATION COVER Total mean vegetation cover of the reclaimed areas was 57.53 percent. Graminoids provided 29.07 percent mean cover (49.42% relative cover), forbs accounted for 26.67 percent mean cover (45.86% relative cover), and six shrub species contributed 1.80 percent mean and 4.72 percent relative cover. The most frequently encountered species were Bromus marginatus (mountain brome), present in 93.3 percent of the 30 transects. Agropyron smithii (western wheatgrass) was present in 83.3 percent of transects while Achillea millefolium (yarrow) was encountered in 60 percent of transects. Penstemon strictus (Rocky Mountain penstemon) was found in 56.7 percent of all transects and Poa pratensis (Kentucky bluegrass) and Agropyron dasystachyum (thickspike wheatgrass) were encountered in 50 percent of all transects. All other species were encountered in fewer than fifty percent of all vegetation cover transects. Overall within the reclaimed areas, the perennial cool season native grass Bromus marginatus was dominant, with a contribution of 11.67 percent mean and 19.27 percent relative cover. Eight additional species encountered during cover sampling contributed three or more percent relative cover, including; Agropyron smithii providing 7.93 percent mean total cover (12.72 % relative cover), Achillea millefolium contributing 5.87 percent mean total and 11.08 percent relative cover, Poa pratensis with 3.60 percent mean (6.17% relative cover), Thermopsis montanus (golden banner) with 2.60 percent mean cover (5.11% relative cover), Mountain Coal Company, LLC West Elk Mine 2011 Reclaimed Areas Vegetation Report Phase II Bond Release Page 7