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related to a competitive effect from Bromus tectorum or another factor is not known at this <br />time. <br />4.3 HERBACEOUS PRODUCTION <br />In 2010, the mean total herbaceous production from Reclamation Area 30 was 7.6 percent <br />less than that predicted. The decrease in total herbaceous production is hypothesized to result <br />from the dominance of small stature annual grass (Bromus tectorum) in the reclamation area. <br />4.4 SPECIES COMPOSITION <br />The Colorado Division of Reclamation, Mining and Safety considers species composition of <br />the revegetated and reclaimed areas to be an indicator of successful vegetation establishment <br />and a diverse vegetation community. The species composition standard requires that there be <br />at least four perennial species, of which three are warm season grasses and one a cool season <br />grass. No one component of the above four species should comprise greater than 40% <br />relative importance nor less than 3% relative importance. Relative importance will be <br />measured by calculating relative cover of the revegetation species. Vegetation species which <br />may be used in the calculation of species composition may be any plant species not defined as <br />a noxious or prohibited plant species, and may be native or introduced. <br />A comparison of the 2009 species composition data from Reclamation Area 30 with the <br />revegetation success standard reveals that there was one qualifying warm season grass species <br />and one qualifying cool season grass species in evaluating the species composition criterion. <br />This year, two warm season grasses and one cool season grass species were present in <br />sufficient relative cover to satisfy the criterion. In 2009, Reclamation Area 30 lacked two <br />qualifying warm season graminoids to meet the species composition success criterion, while <br />2010 data showed that only one qualifying warm season grass species was lacking to meet the <br />final success criterion. This result indicates maturation of the revegetation community and <br />diversification of species composition, even given the adverse growing season in 2010. <br />4.5 COMPARISON OF VEGETATION COMMUNITY TRENDS <br />Direct comparison of the 2010 monitoring data for the areas sampled with that of previous <br />years to evaluate long-term trends in vegetation communities cannot be undertaken for the <br />Reclamation Area 30 as it has only been monitored for two years. The short duration of <br />sampling precludes any significant observations regarding long-term trends at this time. <br />5.0 SUMMARY <br />Quantitative monitoring of Reclamation Area 30 (2006 reclamation) revealed that this area <br />met the requirements for final revegetation success for total vegetation cover and total <br />herbaceous production. One qualifying warm season grass species was lacking to satisfy the <br />species composition criterion. Reclamation Area 30 has shown significant development of a <br />diverse, effective, permanent vegetation cover, and is expected to continue in successful <br />development. <br />Coors Energy Company Keenesburg Mine Page 14 <br />2010 Revegetation Monitoring Keport