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Service. All herbicides and pesticides utilized will be those that are approved by the <br />appropriate state and federal governmental agencies responsible for the approval and <br />distribution of such agents. <br />Weed Management Plan <br />A listing of Colorado's noxious weeds (A, B, and C lists) as well as an indication of Rio <br />Blanco and Moffat Counties' listed taxa are indicated on Table 2.05-10 along with an <br />indication of those taxa that have been observed on or near the Colowyo mine. As indicated <br />on this table, there are no "A" list taxa known from the area. "A" list taxa must be <br />eradicated. To the contrary, there are seven (7) "B" list (must be managed) taxa known from <br />the environs of the Colowyo mine as well as three (3) "C" list (management may be required <br />by local governments) species. Of these 10 species, common mullein and poison hemlock <br />from the "C" list, and Russian olive from the "B" list are not overly problematic and will <br />normally not require attention. In fact the Russian olive was purposefully planted in the <br />reclamation. If "infestations" of common mullein or poison hemlock evolve, they will be <br />treated in the same manner as the more problematic species. <br />The remaining seven species: hoary cress, musk thistle, Canada thistle, bull thistle, <br />houndstongue, black henbane, and downy brome (cheatgrass) will be the primary focus of the <br />program and will likely receive attention as appropriate at the Colowyo mine. Of these seven <br />species, the first six will be specifically targeted for remediation while the seventh, <br />cheatgrass, will be carefully monitored to determine if it becomes problematic in older <br />reclamation*. If it becomes problematic, it will receive similar attention as the other six <br />species. In addition, continued monitoring of reclamation will focus on identification of any <br />new noxious weeds. <br />For the most part, noxious weeds observed on or near Colowyo reclamation do not achieve <br />"infestation" levels. By infestation, Colowyo means: 1) relative cover contribution of one <br />noxious weed species or a combination of noxious weed species exceeding three percent in a <br />revegetated stand; or 2) a "patch" of any listed species in which the noxious weed component <br />exceeds 25% relative cover and occupies an area larger than 100 square feet on any disturbed <br />area. Rather, noxious weeds tend to occur as scattered individuals or small pockets of <br />individuals. This distribution suggests that spot control will be the only effective procedure <br />that can be utilized. <br />To manage these six noxious weed specie populations, Colowyo will either perform itself, or <br />contract out, annual weed control activities. Weed control will typically involve herbicide <br />application at the appropriate rates and during the appropriate life stages (as possible) to <br />effect control. Spot applications will be preferred over "blanket" applications to prevent loss <br />of desirable reclaimed taxa such as seeded forbs and shrubs, however, blanket application <br />may be necessary if any infestation areas are observed. <br />. Although it cannot be discerned with 100% certainty, it appears that cheatgrass patches and populations in Colowyo <br />reclamation, tend to succumb to successional pressure exhibited by the adapted perennials. In this regard, it appears <br />that cheatgrass populations drop off to low levels in mature reclamation. <br />2.05-61 Revision Date: 3/14/08 <br />Revision No.: TR-72