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3.0 RESULTS <br />3.1 Phase II Summary <br />A total of 58 plant species were observed within the Phase II Bond Release area (all or part of 28 <br />revegetated units) evaluated in 2008 (See Plates 1 & 2). These consisted of 24 grass taxa, 26 forbs, 0 <br />sub - shrubs and 8 shrubs (see Table 3 in Appendix A). Table A -1 indicates all taxa observed during <br />fieldwork. Among these taxa is the invasive weed cheatgrass (including Japanese brome), existing as <br />occasional patches. Ground cover in the Phase II Bond Release area (Table 1 and Chart 1) consisted of <br />71.5% live vegetation, 0.5% rock, 22.3% litter, and bare soil exposure of only 5.7 %. Perennial cover <br />across the unit averaged 63.0% (88.1% relative cover) with annual and biennial cover averaging 8.5% <br />absolute cover (11.8% relative cover) and noxious weeds exhibited 0.1% cover. Dominant taxa were <br />thickspike wheatgrass (Agropyron dasystachyum), cicer milkvetch (Astragalus cicel), crested wheatgrass <br />(Agropyron cristatum), riparian wheatgrass ( Agropryon riparium), and Kentucky bluegrass (Poa <br />pratensis), with 14.0 %, 8.4 %, 7.2% 5.3 %, and 5.2% average cover, respectively. With regard to <br />diversity, the Phase II Bond Release Area exhibited 10 perennial grasses and 2 perennial forbs with <br />between 3% and 50% relative cover although achievement of a diversity success criterion is not a <br />requirement of Phase II evaluations. <br />3.2 Reference Areas <br />3.2.1 Mountain Shrub Reference Area <br />The Mountain Shrub Reference Area is comprised of approximately 18 acres of gently to moderately <br />sloping vegetation that has a predominately northwesterly aspect (mesic) and easterly aspect (xeric) (see <br />Plate 3). The Mountain Shrub Reference Area was expanded in 2005 to include the east - facing slope of <br />the ridge to provide representation from the xeric subtype of Mountain Shrub. The purpose of this <br />inclusion is to provide a better representation of the distribution of Mountain Shrub communities located <br />on and around Colowyo properties. The xeric exposure tends to exhibit more elevated herbaceous <br />parameters given a modest reduction in the overstory. This reference area is located on a ridge west of <br />the West Pit Area. <br />A total of 35 plant taxa were observed in this reference area (see Table 3). Ground cover in the <br />Mountain Shrub Reference Area (Table 1) consisted of 63.0% live vegetation, 0.5% rock, 31.3% litter, <br />and bare soil exposure of 5.2 %. Perennial cover across the unit averaged 55.1% with annual and <br />CEDAR CREEK ASSOCIATES, Inc. Page 9 Colowyo Coal Company <br />2008 Phase II Evaluation (Updated Dec -10) <br />