2018-01-03_PERMIT FILE - C1981010A (12)

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accounts for 80.01 percent of the PR -7 Mine Expansion Area and approximately 260.27 acres or 90.13 percent of the projected maximum mine disturbance area. Plant Cover. Total plant cover on this site averaged 61.73 percent and litter cover averaged 34.94 percent. The average total herbaceous plant cover was 34.60 percent with a variance of 101.83. Shrubs were the dominant plant life form encountered on this site, contributing 27.13 percent of the total plant cover and 43.95 percent of the total relative cover. Grasses were the second most dominant plant life form, contributing 19.07 percent of the total plant cover or 30.89 percent of the total relative cover. Perennial forbs contributed 13.53 percent of the total plant cover or 21.92 percent of the total relative cover. Annuals and Biennials contributed 1.20 percent of the total plant cover or 1.94 percent of the total relative cover. Noxious weeds contributed 0.80 percent of the total plant cover or 1.30 percent of the total relative cover found on this area. Mountain Snowberry, a native shrub was the dominant plant species encountered, contributing 21.06 percent of the total relative plant cover found on this site. The other dominant plants encountered were: Kentucky Bluegrass, Gambel Oak, Smooth Bromegrass and Black Chokecherry, which contributed 8.54, 8.10, 8.10 and 5.83 percent, respectively, to the total relative cover on this area. Production. The average air-dry total herbaceous forage production equaled 18.47 g/1/4 m2 (73.88 g/m2 with a variance of 1,044.29) or 658.3 pounds of air-dry forage per acre. Perennial grasses contributed 10.42 g/1/4 m2 or 56.42 percent of the air-dry herbaceous forage. Perennial forbs contributed 6.37 g/1/4 m2 or 34.49 percent of the air-dry herbaceous forage production. Annual grasses contributed 0.99 g/1/4 m2 or 5.36 percent of the air-dry herbaceous forage production. Annual forbs contributed 0.43 g/1/4 m2 or 2.33 percent of the air-dry herbaceous forage production. Noxious weeds contributed 0.27 g/1/4 m2 or 1.46 percent of the air-dry herbaceous forage production. The average oven -dry total herbaceous forage production equaled 17.26 g/1/4 m2 or 615.2 pounds of oven -dry forage per acre. Perennial grasses contributed 9.73 g/1/4 m2 or 56.37 percent of the oven - dry herbaceous forage. Perennial forbs contributed 5.96 g/1/4 m2 or 34.53 percent of the oven -dry herbaceous forage production. Annual grasses contributed 0.94 g/1/4 m2 or 5.45 percent of the oven - dry herbaceous forage production. Annual forbs contributed 0.39 g/1/4 m2 or 2.26 percent of the air- dry herbaceous forage production. Noxious weeds contributed 0.24 g/1/4 m2 or 1.39 percent of the air-dry herbaceous forage production. Shrub Density. The average shrub density equaled 532.57 shrubs per one hundred square meters or 21,553.0 shrubs per acre. Mountain Snowberry, Gambel Oak and Saskatoon Serviceberry were the dominant shrubs encountered. Big Saeebrush Plant Communit This vegetation type is the second largest plant community type found within the PR -7 Mine Expansion Area and covers an area of approximately 54.03 acres and accounts for 6.79 percent of the PR -7 Mine Expansion Area. The Big Sagebrush Plant Community accounts for 6.26 acres or 2.17 percent of the projected maximum mine disturbance area. The largest single area of Big Sagebrush is located on the northern portion of the PR -7 Mine Expansion Area, with smaller blocks located in the central and southern portions of the site. The dominant plant species growing on the Big Sagebrush vegetation type is Mountain Big Sagebrush. 2-122n