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exhibits total production of 387.3 pounds per acre, of which 344.5 pounds were due to perennials (89 %). <br />Noxious weeds contributed a negligible 1.8 pounds per acre that were not included in the total. Mine <br />Area No. 3 exhibits slightly greater total production (397.1 pounds per acre), however, only 204.5 pounds <br />were due to perennials (51 %). In this regard, there is still a stand of Russian thistle that occupies the <br />central portion of the reclaimed unit. However, it appears that this "patch" is shrinking in both size and <br />density as desirable vegetation invades from the perimeter (and from within). As indicated, desirable <br />vegetation is readily observable from within the central "patch" and appears to be expanding dominance. <br />This hypothesis is predicated on the fact that Russian thistle is an early seral invader that cannot <br />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 exhibits a total of only 80.5 pounds per acre of herbaceous vegetation, <br />of which 79.6 (99 %) is perennial. Similarly, Sagebrush Reference Area B exhibits only 93.9 pounds per <br />acre of herbaceous vegetation of which 91.9 (98 %) is perennial. To the contrary, the Grassland <br />Reference Area exhibits substantially greater herbaceous production (250.6 pounds per acre), of which <br />236.7 (94.5 %) is perennial. <br />3.5 2010 Woody Plant Density <br />Although there is no standard or success criterion for woody plant density, data for this variable <br />were easily collected along density belts co- located with ground cover transects. These data were <br />collected (only in 2010) to provide information regarding this variable with respect to the quality of the <br />reclamation as wildlife habitat. In this regard, Mine Area No. 1 exhibits an average density of woody <br />plants of 161.9 per acre. Composition of this stand of woody plants is dominated by four -wing saltbush <br />(Afip /ex canescens) with 139.2 per acre. Three additional species comprise the remainder of the <br />sampled population: big sagebrush, rubber rabbitbrush (Chfywthamnus nauseosus), and Gardner <br />saltbush (A&ipiexgardnerii) with 16.2, 4.9, and 1.6 plants per acre, respectively. <br />Mine Area No. 3 exhibits an average density of woody plants of 229.9 per acre. Composition of this <br />stand of woody plants is also dominated by four -wing saltbush with 145.7 per acre. Only one additional <br />woody plant was observed on Mine Area No. 3 (big sagebrush), and this taxon exhibited 84.2 plants per <br />acre on average. <br />3.6 2010 — General Observations <br />With the exception of some remnant Russian knapweed (Acropolon re ens), the reclaimed areas <br />look to be in reasonably good condition and it is recommended that Year 2 sampling for Phase III release <br />continue in 2011. Knapweed was not sufficiently dense to present more than 0.5% ground cover in Mine <br />CEDAR CREEK ASSOCIATES, Inc. Page 14 Hamilton Mine - Phase III Bond Release <br />Year 1 of 2 <br />