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• Relative cover by lifeform is summarized in Table 18 and graphically presented in Figure <br />5. Data on which this graph is based are presented in Tables 1, 4, 7, 10, 12, and 14. As <br />can be seen in Figure 5, the reclaimed areas are much more strongly dominated by <br />herbaceous species, especially native perennial cool season grasses than the reference <br />areas. In the Aspen, Mountain Brush, and Sagebrush/Snowberry reference areas, the <br />woody biomass supported by one or more centuries' cumulative growth allows only <br />limited growth by herbaceous species. Although the herbaceous component of these <br />native vegetation types is diverse, especially as pertains to perennial forbs, the physical <br />dominance of the woody component leaves little room for herbaceous species' growth <br />(except in the Sagebrush vegetation type). <br />Compared to reference area composition, 1993 reclamation had a comparable portion of <br />total vegetation cover contributed by native perennial forbs. The younger reclamation <br />(1996 and 1998) showed smaller representation of native perennial forbs, but show <br />progress toward that development observed in the seven-year old 1993 reclamation. As <br />of 2000, the contribution of introduced perennial grasses to reclaimed area cover was <br />• small. However, to a much greater degree than introduced perennial forbs, these <br />introduced grass species have serious weedy tendencies and could expand to the <br />detriment of all other life forms (and achievement of diversity and woody plant density <br />performance standards). It should be noted that these introduced perennial grasses are <br />not among the components of the seed mixes used in these areas. Their presence <br />could have come from the topsoil, but they are very rare in native vegeiation, so that is <br />unlikely. They could also have entered topsoil during storage, but nearly all, if not all, of <br />the soils in the 1993, 1996, and 1998 reclamation were "direct -hauled", and so were <br />not stored. The unfortunate conclusion is that seed purchased as a native species <br />includes some seeds of introduced species. In our opinion, the most likely source of <br />intermediate wheatgrass is as undetected impurities in western wheatgrass orchards. <br />The vegetative growth of the two species is quite similar and quite likely scattered <br />intermediate wheatgrass plants among a western wheatgrass planting would go <br />unnoticed unless specifically sought out. A similar situation may well exist with smooth <br />brome impurities in mountain brome orchards. <br />• <br />13 <br />