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I? www.bio-geo.com <br />Dan Mathews of CDRMS, no adjustment was made to the standard deviation of the reclaimed <br />area mean for purposes of statistical comparison with Q. <br />Sample adequacy was demonstrated in the reclaimed area and the reference area. Mean cover <br />in the reclaimed area (25.5%) is less than Q (27.3%). Therefore, the reclaimed area mean was <br />compared to Q using a one-sample "standard null" t-test (see Section 2.3, Statistical Methods, <br />procedure #2). Table 5 shows the values for the t-test. Because t, is less than tt, the null <br />hypothesis is not rejected, the reclaimed area mean is shown to be no less than Q, and <br />revegetation is deemed successful for cover in the Dryland Pasture reclaimed area for 2007. <br />Production, Dryland Pasture 2007 <br />2007 data for each production plot are shown in the following tables in Appendix A: <br />Table Al 1: Production, Dryland Pasture reference area, 2007 <br />Table Al 2: Production, Dryland Pasture reclaimed area, 2007 <br />Table 6, below, shows summary statistics for 2007 production measurements in the Dryland <br />Pasture reference area and the Dryland Pasture reclaimed area, and the statistical data used to <br />compare the reclaimed area means with the standard. <br />Production of undesirable annual plants, mostly forbs, was high in the reference area and <br />relatively lower in the reclaimed area. Broom snakeweed was common in the reference area <br />but absent in the reclaimed area. This sub-shrub is considered by the USDA Natural Resources <br />Conservation Service (NRCS) to be unpalatable to livestock, and it was not included in total <br />production of desirable plants. Production was highly variable in both areas. Sampling in the <br />reference area was terminated after 49 plots with estimated sample adequacy at 60 samples, <br />and sampling in the reclaimed area was terminated after 35 plots with estimated sample <br />adequacy at 65 samples. <br />Comparison to standard. Sample adequacy was not demonstrated in the reference area or in <br />the reclaimed area. The reclaimed area mean (295.8 lb/acre) exceeds Q (135.3 lb/acre), and at <br />least 30 samples were taken in each area. Therefore, the two-sample reverse-null test with <br />Satterthwaite approximations (see Section 2.3, Statistical Methods, procedure #4) was used to <br />compare the reclaimed area mean to Q. Table 6 shows the values for the t-test. Because t, is <br />greater than tt, the null hypothesis is rejected, reclaimed area production is shown to exceed Q, <br />and revegetation is deemed successful for production in the Dryland Pasture reclaimed area for <br />2007. <br />49 <br />16