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• Samples 4 and 5 are examples of seedings that are following a path more typical of reclaimed <br />areas at other mines in the area. Here, native perennial grasses, particularly mountain brome <br />(Ceratochloa carinata), slender wheatgrass (Elymus trachycaulus), western wheatgrass <br />(Pascopyrum smithii), and Agassiz bluegrass (Poa agassizensis) are dominant. Introduced <br />perennial cool season grasses, especially smooth brome (Bromopsis inermis) are also prominent. <br />Inasmuch as these are young stands, annual and biennial species are abundant, only slightly less <br />so than the previously described areas. However, the establishment of native perennial forbs is <br />much better developed. Samples 4 and 5 averaged 6 native perennial forb species per 100 sq. <br />m., compared to an average of less than two species per 100 sq. m. in the other three samples <br />(1, 2, and 3). Alfalfa was moderately abundant in Sample 4 with 8 percent ground cover. <br />Total vegetation cover, averaged over the five samples of very diverse circumstances, was 38.4 <br />percent. Standing dead, litter, bare soil, and rock cover values averaged 0.8, 20.0, 39.8, and 1.2 <br />percent respectively. Species density averaged 23.8 species per 100 sq. m. <br />Production (Table 2) <br />Herbaceous production in the potentially unseeded areas (Samples 1 and 3) was moderately law <br />at from about 400 to 1200 Ib/ac (most of which was annual/biennial forb growth). Sample 3 was <br />highly productive because of the abundance of alfalfa at nearly 4000 Ib/ac Sample 4 was also <br />highly productive at nearly 4800 Iblac because of. extensive growth of alfalfa and smooth brome. <br />Sample 5, without extensive alfalfa or smooth brome, but otherwise similar was much more <br />moderately productive at about 700 Ib/ac. <br />Total herbaceous production averaged over all five samples for alfalfa was 503 Iblac. Total <br />herbaceous production for all species other than alfalfa averaged over all five samples was 1708 <br />pounds per acre. Total herbaceous production averaged 2211 Ib/ac. <br />• Woody Plant Density (Table 3) <br />Shrub growth in the sampled areas was sparse, averaging 73 individuals per acre, with no woody <br />plants at all in Samples 2 and 3. Big sagebrush (Seriphidium tridentatum) contributed more than <br />one-half of this total. Mountain snowberry (Symphoricarpos rotundifolius) was also a major <br />contributor. Wood's rose (Rosa woodsiQ was present in lesser quantities. <br />Sagebrush Reference Area <br />(Photographs 5 through 8) <br />For comparative purposes, the portion of the Yoast Sagebrush Extended Reference Area that lies <br />along the mine access road was sampled. This portion of the Sagebrush ERA is most directly <br />comparable to the roadside areas that were sampled in 1999. <br />Cover (Table 4) <br />Native perennial cool season grass was the dominant lifeform in this area and provided 45.5 <br />percent of total vegetation cover. Western wheatgrass and Agassiz bluegrass each contributed <br />more than one-third of this total. Nelson needlegrass (Achnatherum nelsonir) was also a <br />significant contributor. Six other species made lesser contributions. Native shrubs average 30.0 <br />percent of total vegetation cover. Big sagebrush accounted for more than four-fifths of this total. <br />Alkali sagebrush (Seriphidium arbusculum ssp. longilobum) and Saskatoon serviceberry <br />(Amelanchier alnifolia) also contributed. Native perennial forbs averaged 18.8 percent of total <br />vegetation cover. One-flower woodsunFlower (Helianfhella uniflora) contributed more than one- <br />fourth of this total. Western yarrow (Achilles lanulosa) and Pacific aster (Virgulaster ascendens) <br />each contributed one-fifth of this total. Arrowleaf balsamroot (Balsamorhiza sagittafa) and tailcup <br />lupine (Lupinus caudatus) each contributed approximately one-tenth of this total. Three other <br />species were present in measurable quantities. Native annual and biennial forbs contributed 2.8 <br />percent of total vegetation cover. Douglas knotweed (Polygonum douglasir) was the dominant <br />• species in this lifeform. Linearleaf collomia (Collomia /inearis), bushy birdbeak (Cordylanthus <br />ramosus), and bigfruit willowherb (Epilobium brachycarpum) comprised the balance. Tarweed, <br />an introduced annual and biennial forb, and moss, each accounted for 0.9 percent of total <br />