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area values were basically unchanged from 1990, the reference area standards were noticeably <br />higher. <br />The highest native species density in the reclaimed areas was 18.3 in the 1987 Wolf Creek (the <br />highest 1990 value was 18.9 in the 1983 Wolf Creek). Both of these areas had very sparse cover <br />in the early years. By comparison, at 9.9 species per 100 m2, the 1984 Wadge reclaimed area <br />had the fewest native species of any reclaimed area in 1991, as did the 1983 Wadge reclaimed <br />area in 1990 (9.5 species per 100 m2). The heavy cover of aggressive introduced species typical <br />of the older Wadge reclamation is probably responsible for the lower native species density in the <br />1983 and 1984 Wadge areas. <br />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. In the <br />Wadge Pasture, for example, species density in 1988, 1989, 1990, and 1991 was 19.8, 17.8, <br />20.9, and 21.4 species per 100 m2, respectively. This may reflect a moderation of drought <br />conditions during the spring of 1990 and the year of 1991. <br />• Relative cover by lifeform is graphically presented in Figure 5; data on which this graph is based <br />are presented in Tables 1 through 9. Introduced perennial forbs and grasses comprise a large <br />proportion of vegetation cover of all reclaimed areas, except the youngest. In these latter areas, <br />the two-year old reclamation is dominated by introduced annual and biennial forbs. Native species <br />contribute the largest amount of the vegetation cover in the 1984 Wolf Creek, 1987 Wadge, 1987 <br />Wolf Creek, and 1989 Woli Creek areas. These areas, as discussed above, have either a history of <br />slow-developing grass and alfalfa cover (1984 and 1987 Wolf Creek) or were seeded with mixes <br />that were very low in introduced species (1987 Wadge and 1987 and 1989 Woli Creek), both <br />conditions that allow competition-sensitive native plant species a chance to establish. <br />In no area does Cicer milkvetch appear to be a problem like alfalfa has been in the oldest areas; <br />it's presence as 0.3 to 4.4 percent of total vegetation cover is consistent with a meaningful <br />contribution as a nitrogen fixer, without causing excessive competition for other species. It should <br />be noted that Cicer milkvetch had 3.0 percent cover in 1990 in Wadge Pasture and the figure <br />declined slightly to 2.8 percent in 1991. <br />• <br />18 <br />