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Vegetative litter (prior year's growth, dead wood, and other biologic organic material) <br />comprised 34.80 percent ground cover within the historic record vegetation community. <br />Bare soil accounted for 8.67 percent ground cover in the study area. No rock was <br />encountered during cover sampling. <br />4.1.2 Herbaceous Production <br />Results of herbaceous production sampling in the historic record vegetation community <br />are presented in Table 5. Mean total herbaceous production of the sampled quadrats <br />within the study area was 234.8 g/m2 (2092 lb/ac). The standard deviation of the samples <br />was 55.6 g/m2 and the minimum number of samples to characterize the study area for <br />production was 10. <br />4.1.3 Woody Plant Numbers <br />A census of woody plants present in the historic record study area was undertaken, with <br />results presented in Table 6. Eighty-six individual woody plants were counted in the <br />historic record vegetation community. The dominant woody plant was Symphoricarpos <br />rotundifolius (snowberry) with 51 individuals. Artemesia tridentate (big sagebrush), <br />Chrysothamnus nauseosus (rubber rabbitbrush), Gutierrezia sarothrae (snakeweed), and <br />Amelanchier alnifolia (serviceberry) were the remaining woody plants in the study area. <br />Symphoricarpos rotundifolius is an invader from the understory of the adjacent oakbrush <br />community. Gutierrezia sarothrae and Chrysothamnus nauseosus shrubs are <br />characterized as invaders of open spaces in early successional stages. Artemesia <br />tridentata is a wind borne invader from sagebrush communities to the north and west. <br />The lone Amelanchier alnifolia seedling was identified as an encroachment by the <br />adjacent mountain shrub vegetation community. <br />4.1.4 Species Composition <br />Within the historic record vegetation community cover sampling, two lifeforms were <br />represented; graminoids and forbs. The lifeforms included four perennial grass species, <br />five perennial forbs, four annual fortis, and one biennial forb species. Of the fourteen <br />identified species encountered during cover sampling, six were native; including one <br />grass, and five forbs. The eight introduced species included three grasses and five forbs. <br />Introduced species provided 80.5 percent of the total mean vegetation cover. Seasonality <br />of species was entirely cool season. Table 3 provides a listing and characterization of the <br />plant species encountered during cover sampling at the study area. <br />Six of the fourteen species encountered during cover sampling accounted for greater than <br />three percent relative cover. These species were; Bromus inermis at 58.15 percent <br />relative cover, Agropyron smithii with 9.86 percent relative cover, Poa pratensis provided <br />8.45 percent relative cover, Convolvulus arvensis had 6.24 percent relative cover, <br />Erigeron flagellaris with 6.04 percent relative cover, and Agropyron intermedium <br />contributed 5.03 percent relative cover. Of these six species, three were introduced <br />Mountain Coal Company, LLC Page 7 <br />Historic Record Study Area Vegetation Sampling Report: 2010