2017-02-28_REPORT - C1981028 (30)

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Keenesburg Mine 2016 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. LI Vegetation Cover Total vegetation cover on Reclamation Area 23 averaged 51.6% (Table 1) which was an increase from the 42.2% observed in 2015. However, total native vegetation cover was only 14.0% compared 26.4% in 2015. 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 29.2% and is the value used to compare the Reclamation Area to the Success Standard. The three dominant species on all five transects were cheatgrass (an introduced, cool season, annual grass), prickly lettuce (Lactuca seriola, an introduced annual forb), and sand bluestem (Andropogon hallii, a native warm season perennial grass). These species contributed almost 48% of the average total cover. 6.1.2 Herbaceous Production Total herbaceous production within Reclamation Area 23 averaged 215.9 g/m2 (1,926 lbs/acre) in 2016 (Table 2) which was almost double that observed in 2015 (110.4 g/m2). Annual forbs accounted for 54% of this production, while perennial grasses accounted for 43%. Cheatgrass constituted only 3% of the total production compared to 34% in 2015. Average total production without cheatgrass was 209.3 g/m2 (1,867 lbs/acre). This value (without cheatgrass) was used to compare the Reclamation Area to the Success Standard. 6.1.3 Species Composition Six species from three life forms contributed to the cover data (Table 1) and five other species were encountered along the transects (Appendix A). Eight grasses and three forbs were recorded, nine of which were native and two were introduced (Table 3). There were eight perennial species and three annual species. Both warm and cool season grass species contributed to the cover with four warm season perennial species and one cool season annual species. Relative cover was calculated using both the first and second hit data from each transect. Because noxious species cannot be included in calculations for the species composition standard, relative cover was calculated for both the total vegetation cover and vegetation cover without cheatgrass. Cheatgrass contributed 47.7% of the total relative cover; however, with cheatgrass removed, four other species contributed more than 3% of the relative cover (Table 1) including three warm season perennial native grasses and one annual introduced forb. These species in rank order (highest to lowest) include: prickly lettuce, sand bluestem, blue grama (Bouteloua gracilis), and sand dropseed (Sporobolus cryptandrus). Habitat Management, Inc. 9 October 2016