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_ forbs was 1688 Ibs/acre (dry weight is the standard reporting unit) versus 200- <br />• 400 Ibs/acre estimate for 1991. Following 1991 when cattle and wild horse <br />grazing was excluded, the main herbivore effects were from rabbits. Light to <br />heavy (mostly rabbit) utilization was noted on sample plots. The number of weedy <br />species decreased, especially on topsoil embankments near injection and water <br />wells, but the size of the weedy species increased from 1991. Erosion was <br />minimal at all sites. <br />In addition to the required visual evaluation, circular plots and point intercept line <br />transects were utilized to evaluate topsoil embankments. Results from random <br />circular plots located on three topsoil embankments indicated 66°k 138% in 1991) <br />ground cover for perennial species, weeds 9% (7% in 1991) and bare/rock/litter <br />24% (54% in 1991). 'Table 5-3 presents random circular plot data for percent <br />cover and production (grouped and by species). The average production for all <br />topsoil plots 1141 indicated production of grass was 1355 Ibs/acre; forbs, 333.3 <br />Ibs/acre; and weeds, 79 Ibs/acre. The dominant species were western <br />wheatgrass, green neetilegrass, alfalfa, Lewis flax and Russian thistle. Point <br />intercept line transect data in 1992 for percent cover indicated similar results to <br />circular plots. The following are results from the two methods for percent cover: <br />Circular Plots Point Interceot <br />Grass 41 % 41 <br />Forbs 22 22 <br />Shrubs 3 2 <br />Weeds 9 6 <br />Annual Grass <1 <1 <br />Litter/rock/bare 24 29 <br />38 <br />