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Division of Reclamation, Mining and Safety (Division) staff. Prior to collecting the <br />field data, a map was prepared in the office showing the reclaimed areas. Random <br />points were selected by weighted acreage for each reclaimed parcel to ensure the <br />entire site was covered. A total of 30 randomly located sites were selected and the <br />data was collected until sample adequacy for cover was achieved. <br />Cover <br />Vegetation cover was estimated by the use of the point-intercept method. A laser <br />(ten) point frame was used to minimize instrument error and maximize precision and <br />observer accuracy. Cover transects were 50 meters in length, with ten sample data <br />points collected at 5.0 meter intervals along the transect on the right side of the <br />transect centerline, for a total of 100 points per transect. Transect orientation was <br />determined by navigating with a hand held GPS unit to the next transect point. In no <br />event were transects allowed to extend within ten feet of revegetated area boundaries, <br />to minimize impacts from "edge effect." <br />For statistical purposes, each cover transect served as a sample unit. Data points <br />recorded the first vertical "hit" on vegetation (as determined by the laser point <br />frame), soil (bare ground), rock, or litter. The data were summarized by computing <br />mean cover, relative cover (percent of total vegetation cover attributed to each <br />species), and species composition. Species composition information was computed <br />from vegetation cover data using a ratio of individual species cover to total <br />vegetation cover. <br />Production <br />Biomass production data were obtained using a harvest method. All of the current <br />year's growth included within a one-half square meter quadrat was clipped at each <br />transect. Succulents, noxious weeds, and cushion plants were not clipped. Clipped <br />biomass was placed in paper bags, and dried in Colorado State University's <br />Rangeland Ecosystem Science Laboratory forced air ovens for 24 hours at 105°C. <br />Samples were weighed on an appropriate scale to the nearest tenth of a gram and <br />reported in g/m2 and lbs/acre. Clipped samples less than 0.10 grams were reported as <br />trace samples. Average paper bag weight was subtracted from weighted samples. <br />Sample Adequacy <br />Sample adequacy calculations were made for vegetative cover and production of the <br />sampled reclaimed area. The following formula, accepted by the Division, was used <br />for these calculations: <br />15