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Compared to reference area composition, 1997 reclamation had a comparable portion of total <br />vegetation cover contributed by native perennial (orbs. As of 1999, the contribution of introduced <br />perennial grasses to reclaimed area cover was small. However, to a much greater degree than <br />introduced perennial (orbs, these introduced grass species have serious weedy tendencies and <br />could expand to the detriment of all other life forms (and achievement of diversity and woody <br />plant density performance standards). It should be noted that these introduced perennial grasses <br />are not among the prescribed components of the seed mixes used in these areas. Their <br />presence could have come from the topsoil, but they are very rare in native vegetation, so that is <br />unlikely. They could also have entered topsoil during strorage, but nearly all, if not all, of the soils <br />in the 1995 and 1997 reclamation were "direct -hauled", and so were not stored. The <br />unfortunate conclusion is that seed purchased as a native species Includes some seeds of <br />introduced species. In our opinion, the most likely source of intermediate wheatgrass is as <br />undetected impurities in western wheatgrass orchards. The vegetative growth of the two species <br />is quite similar and quite likely scattered intermediate wheatgrass plants among a western <br />wheatgrass planting would go unnoticed unless specifically sought out. A similar situation may <br />well exist with smooth brome impurities in mountain brome orchards. We recommend that SCC <br />have a sample of its seed mix tested for species content at a seed testing laboratory. <br />Sample Adequacy <br />A summary of sample adequacy calculations for the parameters of cover, herbaceous production, <br />and woody plant density is presented in Table 16 (Appendix 1). As can be seen in this table, the <br />data sets for cover in the extended reference areas all achieved sample adequacy. Reclaimed <br />areas approached adequacy. In the absence of the intention to seek formal bond release, the <br />means from the reclaimed area cover data sets are still very much useful in completing an <br />informal assessment. Means established by sample sets somewhat smaller than those needed <br />• for adequacy are nonetheless good approximation of true means. Herbaceous production and <br />woody plant density data were not collected with a large enough sample size to reach sample <br />adequacy. Again, the approximation of means with a small sample was all that was needed to <br />effectively check status of these parameters in 1999. <br />• <br />10 <br />