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Interceptions of plants below an initial plant interception were tallied separately from <br />"first' hits. <br />Transects were completed in each of the sampling areas shown on Exhibit 10-1, Sheets 1 <br />and 2. Absolute top-layer foliar cover was calculated by dividing the number of <br />interceptions for a particular species or material by the total number of points taken (50). <br />Data shown for each sample in the first column of the cover tables are first hit data; these <br />data and the resulting absolute foliar, litter, rock and bare soil cover calculations are <br />directly useful in performance standard considerations and in soil loss model calculations. <br />In addition, percent relative cover was calculated by species and lifeform and is presented in <br />the middle column of the cover data tables. <br />Absolute all-layer cover was calculated by dividing the number of first and other <br />interceptions for a particular species by the total number of first and other interceptions <br />for the whole sample (ie. 50 plus the number of 'other' hits). These tabulations are shown <br />in the right-most columns of the cover tables. Percent all-layer relative cover was also <br />calculated and presented in the cover tables. All-layer data are most illustrative of the true <br />abundance of a given species in the sampled plant community. • <br />Production Sampling <br />Herbaceous production sampling was accomplished using circular one-half square meter <br />(0.5 m2) quadrats within which all herbaceous growth in a vertical projection was <br />removed by clipping and placed in labeled paper bags. Clipped material was returned to the <br />ESCO laboratory and dried at 105 oC for 24 hours, then weighed to the nearest 0.1 gm. <br />In the 1992 studies, clipping was not undertaken in vegetation types in which significant <br />grazing by domestic livestock had already occurred. These types included Sagebrush, <br />Western Wheatgrass/Alkali Sagebrush, Mesic Drainage, Alkali Sagebrush/Greasewood, and <br />Improved Pasture -Upland. Production sampling in the Sagebrush type was not required <br />because cover data collected from that type in 1992 showed statistical comparability with <br />the Sagebrush data collected in 1990 (see pages 30-32 of this report). Production data <br />from the remaining types will be collected from exclosed plots in 1994. <br />Woody Plant Density Samoling <br />Woody plant density in sampling areas was measured within 1 x 50 m quadrats (shrubs) • <br />and 5 x 50 m quadrats (trees, ie. quaking aspen) oriented along the cover transect (where a <br />2 <br />