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• <br /> <br />species and noxious weeds contributed 36% and 0.0% of the composition, respectively. Perusal of Table <br />V10 indicates that a total of 4 perennial species contributed at least 3% relative cover or composition <br />(3% is the typical lower limit for plant diversity bond release evaluations). Two of those species were <br />grasses, one was a forb, and the remaining one was a shrub. <br />Review of Tables V11 and Chart V3 indicates that the average herbaceous production of this area in <br />2005 was 876 pounds per acre, oven-dry weight. Eighty-seven percent (758 pounds per acre) of the <br />total herbaceous production is attributable to perennials, with grasses contributing 743 lbs./acre, forbs <br />providing 13 lbs./acre, and sub-shrubs adding 2.5 lbs./acre. Thirteen percent (118 pounds per acre) of <br />the total production is attributable to annuals, with grasses contributing 6 lbs./acre and forbs providing <br />112 lbs./acre. Noxious weeds were not found in any of the sampling quadrats in this community. <br />Perusal of Tables V12 and Chart V4 indicates that the estimated woody plant density in this area <br />was 348 woody plants per acre with the shrub lifeform accounting for 100% of the total. Low <br />rabbitbrush was the dominant woody species with 201 plants per acre followed by mountain big <br />sagebrush at 136 per acre. <br />3.3.3 Study Area - Reference Area Comparability <br />Review of Table V2 indicates that the total vegetation ground cover and production for the <br />Grassland baseline study area is comparable to the values obtained from.the Grassland reference area. <br />These comparisons of the "tabular" versus "calculated" t-statistics on Table V2 also indicate success <br />given the Students t-test indicated by the guidelines. A two-sided t-test for two independent samples <br />was considered appropriate and the decision rules for this test were: <br />If 1* t(0.95,n1+n2-2) , conclude that the two areas are unequal, and <br />If 1* < t(o.95,n1+n2-2)r conclude that the two areas are equal (for a = 0.05). <br />The tabular t values for an « = 0.05 and n-2 degrees of freedom (d.f.) and calculation of the <br />• <br />comparison t* statistic for comparison are as follows: <br />Variable <br />Vegetation Cover <br />Production <br />tabular t value <br />1.9944 <br />1.9867 <br />t* statistic <br />1.7482 <br />1.7876 <br />CIEImAR CUM AMO CRATMO, INC. <br />Page 21 <br />2005 Collom Vegetation Survey