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successfully compete with native perennial vegetation over the long term. With time, perennials are able <br />to extirpate this species except for the occasional plant that allows the taxon to persist. <br />Sagebrush Reference Area A exhibited a total of 80.5 pounds per acre of herbaceous vegetation, <br />including 79.6 pounds of perennial production (99 %) in 2010 and 152.7 pounds per acre, all of which <br />was perennial production (100 %) in 2011. Similarly, Sagebrush Reference Area B exhibited 93.9 pounds <br />per acre of herbaceous vegetation, including 91.9 pounds of perennial production (98 %) in 2010 and <br />166.0 pounds per acre, including 164.2 pounds of perennial production (99 %) in 2011. The Grassland <br />Reference Area exhibited substantially greater herbaceous production, 250.6 pounds per acre, including <br />236.7 pounds of perennial production (94 %) in 2010 and 391.7 pounds per acre, including 387.8 pounds <br />of perennial production (99 %) in 2011. <br />3.5 Woody Plant Density <br />Although there is no standard or success criterion for woody plant density, data for this variable was <br />collected along density belts co- located with ground cover transects in 2010. This data was collected to <br />provide information regarding this variable with respect to the quality of the reclamation as wildlife <br />habitat. In this regard, Mine Area No. 1 (Table 24) exhibits an average density of woody plants of 161.9 <br />per acre. Composition of this stand of woody plants is dominated by four -wing saltbush (Atrip /ex <br />canescens) with 139.2 per acre. Three additional species comprise the remainder of the sampled <br />population: big sagebrush, rubber rabbitbrush (Chrysothamnus nauseosus), and Gardner saltbush <br />(Atrip /exgardner /i) with 16.2, 4.9, and 1.6 plants per acre, respectively. <br />Mine Area No. 3 (Table 25) exhibits an average density of woody plants of 229.9 per acre. <br />Composition of this stand of woody plants is also dominated by four -wing saltbush with 145.7 per acre. <br />Only one additional woody plant, big sagebrush, was observed on Mine Area No. 3, and this taxon <br />exhibited 84.2 plants per acre on average. <br />3.6 General Observations <br />With the exception of a few remnant Russian knapweed plants (Acropt / /on repens), the reclaimed <br />areas look to be in very good condition and it is recommended that both Mine Area No. 1 and Mine Area <br />No. 3 be released. Knapweed was not sufficiently dense to present more than 0.5% ground cover in <br />2010 and was down to 0.1% in 2011 for Mine Area No. 1. This weed was not detected by sampling in <br />Mine Area No. 3. It is Cedar Creek's understanding that an active program of knapweed control has <br />reduced the existing population to near zero values. Now that knapweed is controlled on the reclaimed <br />surface, a program of continued maintenance will be necessary for an additional three years to address <br />seed remaining in the soil that can remain viable for that period of time. Remaining reclamation shows a <br />CEDAR CREEK ASSOCIATES, Inc. <br />Page 17 Hamilton Mine - 2011 <br />Phase III Bond Release Evaluation <br />