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density in 1988 through 1996 was 19.8, 17.8, 20.9, 21.4, 21.4, 27.:i, 26.8, 25.6, and 26.8 • <br />species per 100 m2, respectively. The basic stability of total species density through 1994 <br />~ under very severe climatic conditions and in 1995 under very favorable climatic yet, <br />paradoxically, severe competitive conditions, suggests that the gains in species density are <br />durable and that this attribute of the reclaimed area ecosystem is not "fragile." <br />i Examination of Figure 4 reveals that the reclaimed areas approximate the reference areas in the <br />prominence of native perennial forbs and grasses. However, all reclaimed areas also have more <br />~ non-native species than the reference areas. The youngest reclaimed areas have the largest <br />I i number of species of introduced annual (and biennial) forbs. <br />Relative cover by lifeform is summarized in Table 20 and graphically presented in Figure 5. <br />Data on which this graph is based are presented in Tables 1, 4, 7, 10, 13, and 15. Introduced <br />perennial forbs and grasses comprise a large proportion of vegetation cover of all reclaimed <br />areas, including the youngest, the 1992 Reclaimed Area. <br />I <br />II 1996 saw a further decline in native species in the Wadge Pasture, as shown below: • <br />'i Year Percent Relative Cover by Native Species in Wadge Pasture <br />' ~ 1993 22.0 •_ <br />~ 1994 17.9 <br />i 1995 11.5 <br />I <br />1996 7.4 <br />I <br />The aggressiveness of non-native species simply continues to overwhelm native species in <br />Wadge Pasture and other reclaimed areas. The utility of a~ non-native species in the long- <br />' term goals of the reclamation needs to be carefully examined in light of the probability that even <br />small amounts of non-natives in original seed mixes will lead to non-native dominance as they <br />~~ I continue year after year to overwhelm natives. <br />i Cicer milkvetch in 1995 was more abundant than ever before measured in Wadge Pasture at <br />10.7 percent of total vegetation cover. In 1996, it had decreased to 9.2 percent of total <br />~ vegetation cover. This species comprised 4.6 percent of total vegetation cover in 1990 in <br />I <br />r1 <br />U <br />23 <br />