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perennial species, of which three are warm season grasses and one a cool season grass. <br />No one component of the above four species should comprise greater than 40% relative <br />importance nor less than 3% relative importance. Relative importance will be measured <br />by calculating relative cover of the revegetation species. Vegetation species which may <br />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 />Reclamation Area 23 had three qualifying species relative to the final species <br />composition success criterion (Calamoâ–º'ilfa longifolia exceeded the maximum relative <br />cover restriction). While having an adequate number of warm season grasses to meet the <br />standard, the reclamation area lacked a cool season grass to meet the standard. <br />Reclamation Area 29 had three perennial warm season graminoids meeting the species <br />composition requirements this season, but lacked one qualifying perennial cool season <br />graminoid to satisfy all requirements of the final revegetation success criteria for species <br />composition. While both Agropyron smithii and Oryzopsis hymenoides were present in <br />cover sampling this year, the dry winter and spring hindered their cool season growth, <br />rendering their contributions to relative cover, less than in average precipitation years. <br />Reclamation Area 30 had four perennial warm season graminoids and two perennial cool <br />season graminoids meeting the species composition requirements this season, thereby <br />exceeding the final species composition requirement. <br />Reclamation Area 31 had one perennial warm season graminoid and two perennial cool <br />season graminoids meeting the species composition requirements this season, but lacked <br />two qualifying perennial warm season graminoids to satisfy all requirements of the final <br />revegetation success criteria for species composition, not unexpected for a stand in its <br />third growing season. <br />The paucity of cool season species (both graminoids and forbs) this season is attributed to <br />the extremely dry winter and spring of 2012. The lack of moisture during this period <br />resulted in sparse growth and nearly absent anthesis and seed set by cool season <br />graminoids (and forbs) this season. While reduced in biomass production this season, <br />warm season species, by their very presence, were proportionately represented in greater <br />numbers and relative cover this year. <br />With the dry conditions in the winter, spring, and summer of 2012, it is noted that the <br />relative cover of forbs in the reclamation areas was low to non- existent this season. This <br />season forbs were only present in cover sampling in one reclamation area (Reclamation <br />Area 31). The forbs present were Ambrosia psilostachya and Nuttallia nuda <br />(blazingstar), both native perennials, and both with characteristics adapted to more xeric <br />conditions, and Kochia scoparia (kochia), an annual invader of early successional areas <br />(also physiognomically adapted to xeric conditions). Additional support for the <br />observation that the dry precipitation regime in 2012 affected vegetation in the <br />reclamation areas is found in the species numbers encountered during cover sampling. <br />The following table compares lifeforms encountered in cover sampling at the reclamation <br />areas in 2011 and 2012. <br />Coors Energy Company Keenesburg Mine Page 20 <br />2012 Revegetation Monitoring Report <br />