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TRAPPER MINING INC. SAND AND GRAVEL SITE • Exhibit J - Site Asessment for Vegetation Information 1.0 Vegetation Plant canopy cover, frequency of occurrence, maximum plant height, percent mulch cover (litter), and air dry annual plan[ production were estimated. Plant canopy cover was estimated in 150 quadrats of 20 by 50 cm. These were placed at 1-m intervals along three 50-m line transects. Line tran- sects were spaced 20-m apart. Canopy cover was visually estimated into six cover classes as described by Daubenmire. Frequency of occurrence of each plant species was estimated by presence or absence for each quadrat. The tallest plant in each quadrat was measured. Percent mulch cover was visually estimated by cover classes. (See Exhibit C map for location.) Annual plant production was estimated by clipping six .25-m2 plots within the transect boundary. Annual production (air dry) was determined by oven-drying vegetation samples at 65°C for 24 hours. The vegetation on both soil types (AW and Absher) is homogenous with respect to canopy cover, species richness and annual production by occular estimates. Line transec[s were established on Absher soils. The poten- tial plant community on this soil snit is mainly western wheatgrass, alkali bluegrass, Wyoming big sagebrush and black greasewood according to Soil Conservation Service soil survey information. The average annual • production of air dry vegetation ranges from 400 to 800 pounds/acre (SCS production estimate). Thirty-five plant species were identified within the transect area (Table J-1). The major portion of the permit area, which has a mesic moisture regime, is dominated by Kentucky bluegrass (Poa pratensis) and makes up 33% of the plant canopy cover (Table J-2). Other plant species occurring in decreasing order of abundance are western wheatgrass (Agropyron smithii - 12% cover), big sagebrush (Artemisea tridentata - 5% cover silvery lupine (Lupinus artenteus - 4% cover), prickly lettuce (Lactuca serriola - 2% cover dandelion Taxaricum officinole - 2% cover and cheatgrass (Eromus tectorum - 2% cover The total mean plant canopy cover for the sample area was 60.3 percent and litter cover represented 32%. Annual plant production (air dry) ranged from 3,732 kg/ha (3,392 lbs/ac) on plot 1-transect 1 [0 1,560 kg/ha (1,418 lbs/ac) on plot 1-transect 3, with a mean of 2,256 kg/ha (2,050 lbs/ac) for all production plots. Kentucky bluegrass and western wheatgrass made up 95% of the total produc- tion on this site (Table J-3). Mulch cover (air dry) averaged 6,594 kg/ha (5,994 lbs/ac) within the sample area. The mean plant height (tallest plant in each quadrat) was 57.6 cm (22.75 in). • Contd.