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Keenesburg Mine 2015 Vegetation Monitoring Report <br />Figure 5: Cheatgrass Relative Cover 2012 — 2015 <br />M <br />35 <br />30 <br />0 <br />25 <br />0 <br />U 20 <br />C 15 <br />10 <br />0 <br />2012 2015 2012 2015 2012 2014 2015 2012 2014 2015 <br />Area 23 Area 29 Area 30 Area 31 <br />• <br />7. LI Vegetation Cover Trends Over Time <br />Vegetation data have been collected in Reclamation Area 29 since 2006 and in Reclamation Area <br />30 since 2009. These data sets were each started in the third growing season after seeding. They <br />allow for some evaluation of trends over time. <br />In 2006, Reclamation Area 29 was co -dominated by warm season perennial grasses and annual <br />introduced forbs each comprising close to 30% of the relative cover (Table 14, Figure 6). Cool <br />season perennial grasses, annual native forbs, and cheatgrass comprised relatively equal portions <br />of the remaining cover. The seed mixture used in 2003 was 84% warm season grasses and 16% <br />cool season grasses, thus this composition is not unexpected for a recently reclaimed site in this <br />location. Spring 2007 precipitation was almost double the average likely resulting in a flush of <br />annual species germination. However, from 2006 to 2011, the cover of warm season perennial <br />grasses increased along with total cover, and the relative cover of annual species decreased as <br />would be expected in a newly reclaimed area. Warm season grass species thrive when <br />monsoonal precipitation coincides with warm temperatures in the mid to late summer months as <br />is common in Colorado. <br />In 2012, the herbicide treatment appeared to reduce annual species and the drought likely <br />impacted the cool season grasses more than the warm season grasses. While we do not have data <br />for 2013, the prolonged drought likely continued to take its toll on both the warm and cool <br />season grasses; however, warm season species tend to be more drought tolerant and likely fared <br />better. The above average precipitation that came in the fall of 2013 and the spring of 2014 <br />should have benefited the cool season grasses, but the cheatgrass and the annual forbs were <br />likely able to take advantage of that moisture to outcompete the already stressed perennial <br />Habitat Management, Inc. 18 October 2015 <br />