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Post-reclamation lrtvesrigarion <br />was analyzed for the 0-12 inch and 12-24 inch intervals of the N-3 and S-3 test plots. A total <br />of 19 soil samples and 10 refuse samples were collected. <br />Results <br />Data for this study aze presented and discussed below. Figures 2 through 4 and Table 2 present <br />' comparisons of vegetative cover for each test plot for 1992, 1993, and 1995. Figures 5 through <br />7 and Table 3 present comparisons of herbaceous cover for each test plot for 1993 and 1996. <br />Table 4 presents shrub rooting depth measurements, and Table 5 presents the 1990 and 1996 soil <br />data collection results. Appendix A contains representative photographs of the test plots and <br />reference plot during the three data collection periods, Appendix B contains all vegetative cover <br />data by year, and Appendix C contains all herbaceous production data by yeaz. Finally, <br />' Appendix D contains soil sample methods and results for the 1990 and 1996 data. <br />Vegetative Cover <br />' The three years of cover data presented in Figures 2 through 4 illustrates the shifring of the <br />dominant life forms as the vegetation community progressed within the recently seeded (1990) <br />' refuse disposal area. As would be expected, the 1992 vegetation community was dominated by <br />annual forbs (Table 2). [n each plot, annual forbs made up more than 90 percent of the <br />vegetative cover. The primary species was Russian thistle (Salsola iberica) comprising from 79 <br />' to 95 percent of the vegetative cover (Appendix B-1). <br />By the 1993 data collection, the vegetation community showed a progression towazd permanent <br />' species. The data showed a substantial decrease in annual forbs and an increase in perennial <br />grasses (Table 2). However, annual grasses had increased and perennial forbs and shrubs still <br />showed little signs of establishment. All the plots showed a decrease in total vegetative cover, <br />' primarily explained by the substantial decrease in annual forbs. The completely dominating annual <br />forb in 1992, Russian thistle, had decreased to a relatively small component of the 1993 <br />' vegetation community (Appendix B-2). However, these annual forbs were lefr as litter in 1993, <br />increasing the average percent litter cover from 2.1 in 1992 to 40.3 in 1993. <br />' By June of 1995, the vegetation community was again dominated by annuals (Figure 3). <br />Cheatgrass (Bron:us tecrorum) was the primary species, comprising from 37 to 75 percent of the <br />vegetative cover (Appendix B-3). The annual forb tumble mustard (Sisymbrium altissimum) was <br />' also present in high percentages and surpassed cheatgrass in abundance in one test plot. It is felt <br />that the primary reason for the increase in annual species was the above average moisture which <br />was received at the site during the spring and eazly summer of 1995. <br /> <br /> <br />' ~~e-o~~n~rb-wa 9 <br />