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~~~ 0~~ <br />rn rirnnmenml srvmisu uM rnginern <br />acre reference azea of a sagebmsh/gtass type was identified neaz the mine area and <br />sampled for the first time in 1991. This reference azea was sampled again in 1992. <br />In all areas sample locations were randomly selected using randomly generated grid <br />coordinates overlain on a topographic reap. <br />Herbaceous production was determined by harvesting current yeaz's herbaceous <br />vegetation from 0.5-meter-square quadrats. Harvested material was separated by <br />life form (grasses and fortis) and weighed. Representative samples were oven <br />dried to determine moisture content. All green (field) weights were subsequently <br />converted to oven-dry weights. <br />~~ <br />~,s J1~" ~ ' Vegetation cover transects were located in conjunction with production quadrats. <br />,~-' ~` ,cF"~~ Transects were 30 meters long. Azimuths from the point of beginning of each <br />5A,- ~; ~`'~ transect were randomly determined. An "optical bar" was used to determine "hits" <br />at 20-centimeter intervals. The optical bar is a frame holding five specially <br />designed non-magnifying telescopes. The optical bar is mounted on a tripod and is <br />used essentially like a point frame. The telescopes are aimed vertically toward the <br />ground. The intersection of the cross-hays in each te]escope defines a "point" or <br />hit. Each hit is recorded as a vegetation species, rock, litter or bare ground. Each <br />transect comprised 50 hits. <br />Sample adequacy was calculated for the reference areas and for the reclaimed area <br />for vegetation cover and herbaceous production in accordance with the Division's <br />guideline. Sample adequacy was achieved for vegetation cover in all areas, and for <br />herbaceous production in the Grassy Creek reclaimed area and the reference area. <br />Sample adequacy was not achieved for production in the Eilts' reclaimed area. <br />Sampling for production in this area was discontinued at 50 quadrats. <br />Means for vegetation cover and herbaceous production in the Grassy Creek <br />reclaimed area exceeded the corresponding reference area means. Because the <br />Eilts' reclaimed area will not be compared to the sagebrush/grass reference area, no <br />statistical comparison was made for herbaceous production between these two <br />areas. <br />Results <br />Summary statistics and revegetation success criteria are shown in Table 1. <br />Vegetation cover data are summarized in Table 2. Table 2 shows absolute and <br />relative vegetation cover averaged over all transects for each sampled area. Raw <br />data for herbaceous production and total vegetation cover are shown in Tables 3 <br />and 4, respectively. <br />-2- <br />