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1 <br />1 <br /> <br />The dominant vegetation lifeform in the historic record vegetation community was <br />graminoids. The dominant gtaminoid species in the study area was Bromus inermis at <br />15.60 percent mean cover (43.43% relative cover). The two sub-dominant graminoid <br />species in the historic record vegetation community were Poa pratensis with 11.07 <br />percent mean cover (26.91 % relative cover) and Agropyron intermedium at 8.53 <br />percent mean cover (22.63% relative cover). One fort species, Convovuius arrensis at <br />2.40 percent mean wver (5.50% relative cover), provided greater than 3% relative <br />cover. <br />Vegetative litter (prior years growth, dead wood, and other biologic organic material) <br />' comprised 48.27 percent ground cover within the historic rewrd study area. Bare soil <br />accounted for 13.47 percent ground cover in the study area. No rock was encountered <br />in the study azea. <br />1 Herbaceous Production <br />' Results of herbaceous production sampling in the historic record vegetation community <br />are presented in Table 6. Mean total herbaceous production of the sampled quadrats on <br />' the study azea was 127.71 g/m2 (1138.41 16/ac). Herbaceous production quadrat <br />weights were fairly consistent, with the standard deviation being 36.05 percent of the <br />value of the herbaceous production mean. This consistency is likely due to the fact that <br />' this community was once cultivated for grazing or agriculture, which required <br />maintenance of a relatively dense and uniform stand for forage production. <br />' Woody Plant Density <br />No woody plant species were encountered during cover sampling. However, the total <br />' number of woody plants present in the historic record study area was counted (Table <br />7). Sixty-two individual woody plants occurred in the vegetation community. The <br />dominant woody plant was Symphoricarpos rotundifotius (snowberry) with 58 <br />' individuals. GutierreDa sarothrae (snakeweed), Artemesia tridentate (big sagebrush), <br />and Chrysothamnus nauseosus (Rubber rabbitbrush) were the remaining woody plants <br />in the study area. Symphoricarpos rotundi(olius is an invader from the adjacent <br />' oakbrush community. Gutierrezia sarothrae and Chrysothamnus nauseosus shrubs are <br />characterized as invaders of open spaces in early successional stages. Artemesia <br />' tridentate is a wind borne invader from sagebrush communities to the north and west. <br />Species Composition <br />' Within the historic record vegetation community cover sampling, two lifeforms were <br />represented; graminoids, and fortis. The lifeforms included four species of perennial <br />' grasses, one perennial forb, and one annual forb. Of the six species encountered <br />during cover sampling, two were native (Agropyron smithii and Erigeron bagel/aris) <br />and four were introduced (three grasses and one forb). As would be expected in a <br />' vegetation community established for grazing and agriculture, introduced species <br />' -14- <br />