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• IV. DISCUSSION AND CONCLUSIONS Areas revegetated in 1985, 1986, and 1987 were quantitatively sampled in 1996 to evaluate revegetation establishment for Phase II bond release purposes. The Osgood Sand Reference Area was also quantitatively sampled to provide the revegetation success criteria values for vegetation cover for the reclaimed areas governed by the requirements of Rule 4.15.8. In addition to the du•ect comparisons to revegetation success criteria for total vegetation cover and species composition, comparisons were made to the same parameters sampled in 1994 and 1995. Tables 6 and 7 provide comparisons of 1994, 1995, and 1996 sampling parameter values. VEGETATION COVER Total vegetation cover on all areas sampled in 1996 was significantly lower than in the 1995 sampling (Savage and Savage, 1995) but still higher than that recorded in 1994 (Savage and Savage, 1994). In 1996, total vegetation cover on the Osgood Sand Reference Area exhibited a decrease of 19 percent from the 1995 cover values. Correspondingly, the 1985 Reclamation Area exhibited a 52 percent decrease from 1995, the 1986 Reclamation Area showed a 28 percent decrease from the 1995 cover values, and the 1987 Reclamation Area exhibited a 22 percent decrease in total cover • from that sampled in 1995. The reclaimed area exhibiting the lowest vegetation cover during the 1996 sampling was the 1985 Reclamation Area with 31.20 percent total vegetative cover. The 1987 Reclamation Area exhibited the highest level of total vegetation cover with 37.73 percent. The total percent spread in cover for the three reclamation areas for 1996 was 6.53 percent. Based on the quantitative statistical Students t-test, the vegetation cover on the 1986 and 1987 Reclamation Areas was not significantly less than 90 percent of the Osgood Sand Reference Area cover in 1996. Therefore, based on the 1996 total vegetation cover data alone, the 1986 and 1987 Reclamation Areas would meet the final revegetation success criterion for cover. While the 1985 Reclamation Area did not meet the total vegetation revegetation success criterion in 1996, the 1985 Reclamation Area remains eligible for Phase II bond release. The 1985 Reclamation Area met the total vegetation cover revegetation success criterion in both 1994 and 1995 (Savage and Savage, 1994, Savage and Savage, 1995). A review of relative cover characteristics in the revegetated areas and the Osgood Sand Reference Area from 1994 through 1996 illustrates a developmental trend in the 1985 Reclamation Area which explains the low cover values in 1996. Table 6 presents the relative cover by plant species for each area sampled in 1994, 1995, and 1996. • _12_