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• areas. It would appear that there has been a slight decrease in species density in many of the <br /> areas in 1989, compared to 1988, with an average loss of about 2 native species and 2 to 3 <br /> introduced species. It would appear that these were generally annual species, both native ant <br /> introduced. The Wadge pasture (Area D) has, as with cover and production, experienced a less <br /> pronounced decline, having lost about one native species and one introduced species per average <br /> 100 sq. m. <br /> Relative cover by lifeform is graphically presented in Figure 5; data on which this graph is <br /> based are presented in Tables 1 through 10. In the older reclamation (Areas A, B, C, and D), the <br /> species present in greatest abundance are mostly introduced. In the newer reclamation of Areas <br /> E, F, G, and H, the distribution of abundance is much more equitable. In the latter, between a <br /> third and a half of the vegetation cover is comprised of native species. In the older reclamation, <br /> the native component is only 10 to 20 percent of the vegetation cover (and only about 1 percent <br /> in the pre-law Area A). <br /> In the older reclamation, the bulk of the substantial introduced species component is comprised <br /> • of alfalfa, intermediate wheatgrass, and smooth brome. In later reclamation (see Areas E and G), <br /> the proportion of total vegetation cover occupied by introduced perennial (orbs has been reduced, <br /> by virtue of much lower seeding rates, but the introduced perennial grass component, primarily <br /> intermediate wheatgrass, is still abundant. In no area does Cicer milkvetch appear to be a <br /> problem like alfalfa in the older reclamation; it's presence as 2 to 7 percent of total vegetation <br /> cover is consistent with a meaningful contribution as a nitrogen fixer, without excessive <br /> competition with other species. <br /> As mentioned above, the considerable presence of diverse native species in Areas E through H <br /> holds the promise of an increased native presence as these stands mature. The annual fort <br /> component is expected to decline in the next few years; hopefully, the native perennial species <br /> present will fill the void. It would appear that, under the stressed conditions of the past few <br /> years, that native invasion has not been especially active; perhaps following the drop in cover <br /> resulting from the recent drought conditions, an invasion of native species could occur upon <br /> return of more favorable moisture conditions. It should be noted that during the 1989 sampling, <br /> 18 new native species were found in the reclaimed areas that were not observed in 1988. Also <br /> • seven native species that were found in 1988 were not found in 1989, leaving a net increase of <br /> 23 <br />