2015-10-13_REVISION - C1981014 (18)

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Species Diversity. Warm season grass species contributed 4.71% of the total plant cover or 16.44% of the total relative cover. The two most dominant warm season plant species contributed 4.53% of the total plant cover or 15.81% of the total relative plant cover. The four most dominant plant species contributed 20.70% of the total plant cover or 72.25% of the total relative plant cover. When this area was sampled in 2008, IME found that all warm season grass species contributed 2.80% of the total plant cover or 12.14% of the total relative cover. The two most dominant warm season plant species contributed 2.40% of the total plant cover or 10.40% of the total relative plant cover. The four most dominant plant species contributed 15.07% of the total plant cover or 65.32% of the total relative plant cover. Shrub Density. The results obtained from the sampling of the 30 shrub density are found in Table 11, New Portal Reference Area - 2013 Shrub Density. This table shows that the woody plant density averaged 30.47 woody plants per 20 m2 or 6,164.9 woody plants per acre. The locations of the 30 shrub density transects sampled on this site are shown on Map 12, New Mine Portal Reference Area - 2013 Transect Location Map. The sample adequacy calculations in Table 2, 2013 - Statistical Summary and Sample Adequacy Calculations, document that the number of samples required to characterize the parameter of woody plant density at the 90% confidence interval was 21.7 transects. When IME initially sampled this area in 2008, the average woody plant density was 157.7 shrubs per 100 m` or 6,375.6 woody plants per acre which is very similar to the 6,164.9 woody plants obtained in the 2013 sampling VENTO PORTAL RECLAMATION STUDY AREA Plant Cover. The results obtained from the 2013 sampling of the 15 plant cover transects on the Vento Portal Reclamation Study Area, are presented in Table 12, Vento Portal Reclamation - 2013 Plant Cover. "Total plant cover" averaged 44.33% and litter cover averaged 31.47%. "Allowable plant cover" averaged 42.33%. Perennial grasses was the dominant plant life form contributing 35.53% of the total plant cover or 82.41% of the total relative plant cover on these reclaimed areas. Woody plants was the second most dominant plant life form contributing 5.47% of the total plant cover or 12.33% of the total relative plant cover. Annuals and Biennials was the third most dominant plant category, contributing 1.67% of the total plant cover or 4.76% of the total relative plant cover. Noxious weeds was the fourth most dominant cover, contributing 0.40% of the total plant cover and 0.90% of the total relative plant cover. Perennial forbs was the next most dominant plant form, contributing 0.27% of the total plant cover or 0.60% of the total relative plant cover. The most dominant plant species was Western Wheatgrass which contributed 12.37% of the total plant cover or 28.72% of the total relative plant cover. Sand Dropseed, was the second most dominant plant species, contributing 8.53% of the total plant cover or 19.25% of the total relative plant cover. The third most dominant species was Sideoats Grama, which contributed 7.86% of the total plant cover or 17.75% of the total relative plant cover. Blue Grama, was the fourth most dominant plant, contributing 4.53% of the total plant cover or 10.23% of the total relative plant cover. When IME sampled a large portion of this area in 2010, the average "total plant cover" was 60.30%. When IME sampled this area in 2006, the "total plant cover" averaged 42.53%. 13