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Whereas there was observed, in 1989, a slight decline in total species density in general, that <br />trend, as with cover and production was reversed in 1990 and continued upward in 1991 and <br />stabilized in 1992. In Wadge Pasture, for example, species density in 1988, 1989, 1990, <br />1991, 1992, and 1993 was 19.8, 17.8, 20.9, 21.4, 21.4, and 27.5 species per 100 m2, <br />respectively. <br />Relative cover by lifeform is summarized in Table 25 and graphically presented in Figure 5. <br />Data on which this graph is based are presented in Tables 1, 2, 5, 8, 70, 13, 16, 19, and 21. <br />Introduced perennial (orbs and grasses comprise a large proportion of vegetation cover of all <br />reclaimed areas, except the youngest, the 1991 Reclaimed Area. In Phis latter area, the lwo- <br />year old reclamation is dominated by introduced annual and biennial forbs, as is typical of <br />reseeded areas of this age. Native species contributed the largest amount of the vegetation cover <br />in the PECOCO Pasture and 1989 Reclaimed Area. Note, however, that the PECOCO Pasture <br />includesd both reclaimed and native vegetation in the sampled area. 1993 saw a rapid <br />development of native species in the Wadge Pasture also, as relative cover by natives rose from <br />13.4 percent in 1992 to 22.0 percent in 1993. Most of this increase was contributed by <br />greater abundance of native annual and perennial forbs and shrubs; native perennial grasses <br />actually declined slightly in 1993. <br />1992 seems to have been a good year for cicer milkvetch; in almost all areas, its abundance was <br />greater than in 1991. For example, cicer milkvetch had 4.6 percent of total vegetation cover in <br />1990 in Wadge Pasture and the figure declined slightly to 3.6 percent of total vegetation cover <br />in 1991, but in 1992, the figure rose to 6.7 percent of total vegetation cover and continued at <br />6.6 percent of total vegetation cover in 1993. In the 1993 observations of the 1989 Reclaimed <br />Areas, cicer milkvetch was 1.0 percent of total vegetation cover, compared to 0.0 and 0.4 <br />percent of total vegetation cover in the 1989 Wadge and 1989 Wolf Creek Reclaimed Areas, <br />respectively in the 1991 observations. <br />Despite the 1992/1993 increases, in no area sampled in 1992 or 1993 does cicer milkvetch <br />appear to be a major component like alfalfa has been in the oldest areas; its general presence as <br />1 to 6 percent of total vegetation cover is probably consistent with a meaningful contribution as <br />a nitrogen fixer, without causing excessive competition for other species. <br /> <br />30 <br />