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wildrye, with 24.0%, 6.5%, 5.7%, and 4.3% average cover, respectively. With regard to diversity, the <br />Phase III Bond Release Area exhibited 7 perennial grasses and 2 perennial forbs with between 3% and <br />50% relative cover. Total relative cover for all perennial forbs in the Phase III area was 15.4%. <br />Table 5 displays the results from 16 shrub patches that occupy 27.64 acres of the 780.7 acres of <br />Phase III revegetation (3.6%). The shrub patches exhibit an average of 419.6 woody plants per acre. <br />Table 7 exhibits the results from 45 belt transects collected at each sample site for woody plant density <br />within grassland areas. Perusal of the table reveals that there is an average of 42.3 woody plants per <br />acre in the Phase III bond release area external to shrub patches. Current annual herbaceous production <br />across the Phase III area averaged 1966.8 pounds per acre in 2008 with perennial grasses the dominant <br />category (see Table 3). <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 />Plates 5 and 6). The Mountain Shrub Reference Area was expanded in 2005 to include the east-facing <br />slope of the ridge to provide representation from the xeric subtype of the Mountain Shrub community. <br />The purpose of this inclusion is to provide a better representation of the distribution of Mountain Shrub <br />communities located on and around Colowyo properties. The xeric exposure tends to exhibit more <br />elevated herbaceous parameters given a modest reduction in the overstory. This reference area is <br />located on the undisturbed ridge immediately west of the West Pit Area (see Maps 3 and 4). <br />A total of 34 plant taxa were observed in this reference area evaluated in 2007. Current annual <br />herbaceous production across the area averaged 717.5 pounds per acre in 2007 with perennial grasses <br />the dominant category (see Table 3). Ground cover in the Mountain Shrub Reference Area (Table 1) <br />consisted of 56.4% live vegetation, 0.7% rock, 33.6% litter, and bare soil exposure of 9.4%. Perennial <br />cover across the unit averaged 51.4% with annual and biennial cover averaging 5.0%. Dominant taxa <br />were Mountain big sagebrush, bluegrass (Poa agasizensis), slender wheatgrass, Nelson's needlegrass <br />(Stipa neisonii), and cheatgrass with 11.3%, 7.8%, 6.3%, 5.4%, and 4.6% average cover, respectively. <br />With regard to diversity, the Mountain Shrub Reference Area exhibited 6 perennial grasses and no <br />perennial forbs with between 3% and 50% relative cover. Total relative cover for all perennial forbs in <br />the Mountain Shrub reference area was 3.8%. <br />CEDAR CREEK ASSOCIATES, Inc. Page 10 Colowyo Coal Company <br />2008 Phase III Bond Release Evaluation