1987-12-01_PERMIT FILE - C1981017 (290)

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7� inmanouncain.)oiL, Mid-Continent Resources Inc. Coal Basin Mines Steep Spoil Revegetation Test Plots On August 13 and 14, 1987, vegetation cover and production were measured on three- year-old plots established on steep spoil slopes at three separate subalpine locations at Mid-Continent's Coal Basin mines. Eight plots were established altogether. Plot locations are designated Mine #1, Mine #4 and Mine #5. Three 50 foot by 100 foot plots were established at the Mine#4 and Mine#5 locations; two 50 foot by 150 foot plots were established at Mine #1. Each plot was seeded,fertilized and mulched in September, 1984. The seed mixture used at all plots was identical. Further details of the establishment of the plots, including maps showing plot locations and layout, have been transmitted previously to the Division of Mined Land Reclamation. Transect and Quadrat Sampling Methods Vegetation cover was measured in each plot using two 50-foot line transects. Transects • were delineated using a tape measure stretched across the plots about two feet above the ground. At one-foot intervals along each transect, a pin was lowered vertically from the tape toward the ground. Whatever was touched first by the point of the pin was recorded as a "hit'—a species of plant, plant litter, or bare ground or rock. One hundred hits were recorded in each plot. Vegetation production was measured using 0.25 m2 quadrats. Quadrats were located at five-foot intervals along each of the 50-foot vegetation cover line transects—ten quadrats per transect. Within each quadrat, the green weight of each plant species was visually estimated. Prior to making production estimates, samples of grasses and forbs from outside the plots were estimated,clipped and weighed. This was repeated several times to allow each observer to become sufficiently "calibrated" for making accurate visual production estimates under existing field conditions. Grass and forb samples were returned from the field to determine oven-dry moisture percentage. Field estimates of green weight production were subsequently converted to oven-dry weights. Sampling Results Table 1 shows the vegetation cover data by plot. Vegetation cover ranges from 4 percent to 52 percent. Table 2 summarizes these data for each location and over all locations. Mean vegetation cover is 37.0 percent, 47.7 percent and 19.3 percent for Mine#1, Mine#4 and Mine#5, respectively, and 34.4 percent averaged over all plots. Expressing these data as relative cover reveals orchardgrass as the most abundant species, predominant at five of the eight plots, and contributing 26.2 percent of the total vegetation cover overall. (Table 5 gives a listing of common and scientific plant names.) Bromar brome and timothy contribute 13.1 percent and 10.9 percent relative cover, respectively, averaged over all plots. Sheep fescue and canby bluegrass