2009-01-30_GENERAL DOCUMENTS - C1982057

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0 METHODS Phase I Study - Literature Review and Study Design In an attempt to overcome the obstacles of native shrub establishment on reclaimed lands, the DMG requested funding to further evaluate shrub establishment techniques. Funds were appropriated from the State Severance tax fund. DMG signed an agreement with Colorado State University (CSU) to conduct the research. The project was divided into two phases. Phase I included a comprehensive literature review (Paschke et a1. 2003) on the shrub species of interest and development of a study design. Phase II is a field study using demonstration plots. The literature review in Phase I covered the biology, ecology, and propagation of seven species that are of primary importance for wildlife habitat in Colorado. These are: big sagebrush (Artemisia tridentata), antelope bitterbrush (Purshia tridentata), Saskatoon serviceberry (Amelanchier alnifolia), black chokecherry (Prunus virginiana), mountain mahogany (Cercocarpus montanus), snowberry (Symphoricarpos sp.) and Gambel oak (Quercus gambelii). During Phase I representatives of the DMG, the Colorado Division of Wildlife (DOW), CSU researchers and mining companies toured northwestern Colorado surface coal mines to observe different shrub techniques that had been attempted at each mine. Based on the literature review, the field visits and several meetings amongst all parties, a field study was developed. Factors that were consider in designing the demonstration plots were topsoil replacement depth, seeding/planting techniques, species to be planted including their palatability, surface manipulations, and protection from wildlife. In addition, time of planting, growth medium characteristics and climate were recognized as factors that would influence outcomes. The approach used in these demonstration plots differs from normal reclamation techniques, which generally only include replacing a uniform depth of topsoil, drill seeding large areas with one seed mix dominated by grasses, and no fencing to control wildlife damage to shrubs. Phase II - Field Study The mines that volunteered to participate in the field study are all large surface mines in northwestern Colorado: the Colowyo Mine, the Seneca Mine, and the Trapper Mine. All three mines are in dense mountain shrublands that provide valuable wildlife habitat. Elevations range from 6500 to 8100 feet at the mines. Local climate is characteristic of semi-arid steppe regions with average precipitation ranging from 16.1 inches to 18 inches at the mines, and increases with local elevation. Soils are typical of soils found in cold, semi-arid regions of the western United States. They are moderately deep (20 to 40 inches) to shallow (10-20 inches). The dominant vegetation types are sagebrush grasslands and mountain shrublands. Current and historic land uses in the vicinity of these operations is grazing for livestock, and wildlife habitat. Herds of mule deer and elk are common, especially on reclaimed areas during the winter. The treatments used in the field study are designed to overcome the two primary obstacles to shrub establishment - competition from aggressive herbaceous species and browsing. The herbaceous competition is primarily from introduced cool season grass species. These species are reliable and serve as quick erosion control. They thrive where topsoil is replaced and become well established, often at the expense of other desirable species. Seed mixes for the demonstration plots were carefully evaluated to eliminate the competitive introduced species and include native species. Strip seeding was used to isolate the shrub species to further reduce competition from the herbaceous species. Topsoil depths were varied and included seeding directly on spoil. This was done to reduce the competition from herbaceous species that thrive where topsoil has been replaced and to better represent the rocky substrate found in the typical habitat of several of the shrub species. 0