2010-11-01_REVISION - C1981019 (2)

Home Browse Search

RULE 4 PERFORMANCE STANDARDS This method of analyzing diversity was applied to the weighted premine vegetation cover data originally sampled and summarized in Section 2.04.10 on Table 2.04.10-2, 1980 Herbaceous Cover by Species. The percent contribution to diversity by each species contained within the predominate vegetation communities, sagebrush and mountain shrub is weighted by acres and summarized on the revised Table 4.15-7, Premine Species Diversity. A total of four species with a combined contribution to diversity of 43.4% have been chosen to characterize the premine vegetative community diversity standard. The vegetative species with their contribution to diversity are as follows: Species (1) Poapratenensis (2) Agropyron Smithii (3) Achillea lanulosa (4) Stipa virdiula % Contribution to Diversity 22.6% 10.8% 6.7% 3.3% 43.4% Although Gallium and Lupinus caudatus rank reasonably well in the diversity scale, they are not included in the diversity goals for reclamation. Gallium is an annual, while Lupinus caudatus is considered toxic to livestock and is most likely a product of overgrazing. Colowyo is interested in reclaiming with vegetation species with equal or superior utility for the postmining land use when compared with the utility of the naturally occurring premine vegetation. Neither species provides any utility towards supporting the premining land use. Three of the species are perennial cool season greases and one specie is a perennial forb. All of the species are found throughout the premine area on all soil types and moisture regimes. The grass species all provide the qualities for excellent erosion stock use. All four species of vegetation exhibit high utility towards the premine land use. It is important to note that the species exhibiting the greatest contribution to the premine vegetative diversity is the Kentucky Bluegrass, Poa pratensis, which is not considered a native. It exhibits nearly 23% of the diversity, over twice that of the next dominant species, Western Wheatgrass, Agroppyron smi hii, at nearly 11%. Kentucky Bluegrass is an excellent example of how introduced grass species can be a valuable component of a postmining vegetative community just as they are in the premining vegetative community. Species diversity for the postmine vegetative community will be determined in the same manner as the premine inventory. Cover data will be collected using a point frame placed at random points along randomly located transects. Overall, postmine data collection methods will duplicate premine data collection methods. The revegetation objective for diversity will be to establish a community on the reclaimed areas that contain the following; a) At least four principle species including a minimum of three cool season perennial grasses and a minimum of 1 perennial forb. b) Each principal species shall contribute no less than 3% relative cover c) No single species shall contribute in excess of 50% relative cover. Rule 4 Performance Standards 4.15-11 Revision Date: 10/27/10 Revision No.: MR-103