2016-02-29_REPORT - C1981028 (12)

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Keenesburg Mine 2015 Vegetation Monitoring Report 6 RESULTS 6.1 Reclamation Area 23 Reclamation Area 23 is a 0.7 -acre parcel that was formerly part of the B Pit mining area. This area was graded to blend into the reclaimed mining and operational areas to the east resulting in an almost flat east -facing slope. Final revegetation seeding with the DRMS-approved permanent seed mixture took place in November 2002. Because this area is small, only five cover and production samples were taken. 6.1.1 Vegetation Cover Total vegetation cover on Reclamation Area 23 averaged 42.4% (Table 1); however, total native vegetation cover was only 26.4%. The reclamation success standard allows non-native species to be included in the total cover value, but not those listed on the Colorado noxious weed list. Because cheatgrass (Bromus tectorum) is on the weed list, it was removed from the average total cover. This reduced the average total cover to 31.6% and is the value used to compare the Reclamation Area to the Success Standard. The two dominant species on all five transects were sand bluestem (Andropogon hallii), a native warm season perennial grass, and cheatgrass, an introduced, cool season, annual grass. These two species along with sand dropseed (Sporobolous cryptandrus, a native warm season perennial grass), prickly lettuce (Lactuca seriola, an introduced annual forb), and Canadian horseweed (Conyza canadensis, a native annual forb) which were also hit on all five transects, contributed 39.2% of the average total cover. 6.1.2 Herbaceous Production Total herbaceous production within Reclamation Area 23 averaged 110.4 g/m2 (985 lbs/acre) in 2015 (Table 2). Annual forbs and annual grasses each accounted for 34% of this production, while perennial grasses accounted for 32%. Cheatgrass constituted 34% of the total production and average total production without cheatgrass was 78.8 g/m2 (703 lbs/acre). This value (without cheatgrass) was used to compare the Reclamation Area to the Success Standard. 6.1.3 Species Composition A total of seven life forms and 11 species contributed to the cover data (Table 1) and four other species were encountered along the transects (Appendix A). Seven grasses and four forbs contributed to the cover data, nine of which were native and two were introduced (Table 3). There were six perennial species and five annual species. Both warm and cool season grass species contributed to the cover, with four warm season species and three cool season species two of which were annual. Relative cover was calculated using both the first and second hit data from each transect. Five species contributed more than 3% of the relative cover (Table 1) including two warm season perennial native grasses, one cool season annual introduced grass, one annual introduced forb, and one annual native forb. These species in rank order (highest to lowest) include: sand bluestem, cheatgrass, Canadian horseweed, sand dropseed, and prickly lettuce. Habitat Management, Inc. 8 October 2015