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2.0 RESULTS <br />2.1 Overall Summary <br />Overall, a total of 104 plant species were observed within the 16 areas (i4 revegetated units and 2 <br />reference areas) evaluated in 2005. These consisted of 33 grass taxa, 56 fortis, and 15 shrubs (see Table <br />AB-1 in Appendix AB). Table 19 indicates all taxa observed during fieldwork and is the only table that <br />indicates 1) common names, 2) historic scientific nomenclature, and 3) most current taxonomic <br />nomenclature. Remaining tables do not indicate this latter category. On average, 29 unique plant <br />species are observable in any given revegetation unit and 36 in the references areas. Among these taxa <br />are an occasional noxious or invasive weed such as musk thistle or Japanese brome, with the latter <br />occasionally existing as more notable patches. Due to the increased moisture the previous spring, winter, <br />and fall; both annual and perennial plant vigor and growth had noticeably increased over 2004 levels. For <br />example, production in the Reference Areas in 2005 was over double that exhibited in 2004. On the <br />negative side, annual brome levels were also very high this year as evidenced by the increase in <br />cheatgrass and Japanese brome cover from 0.3% in 2004 to 6.1% in 2005. <br />An analysis of the ground cover variable (Charts 3 and 4) indicated that all areas of older <br />reclamation (7 years of age) substantially exceed the success criterion based on 2005 reference area <br />values. Similarly, Table 1 and Chart 5 indicate even greater success with regard to production on the <br />revegetated units that are 7 years of age. With regard to ground cover on areas exhibiting four years of <br />growth, 25% have exceeded the reference area based success criterion, None of the two-year old <br />revegetated units currently pass comparison with the ground cover success criterion. Production data are <br />not collected from younger areas, but eventual success is readily expected. <br />With regard to diversity, Colowyo's revegetation efforts appear to be very strong as indicated on <br />Table 3 and Charts 8 and 9. As observable on these exhibits, diversity tends to increase with the age of <br />reclamation and in most cases should be sufficient for bond release testing by the time they are of <br />sufficient age for such testing (years 9 and 10 of the bond responsibility period). As indicated on Chart 9, <br />all of the areas revegetated in 1998 would pass such testing; 50% of 2001 revegetation efforts would <br />currently pass diversity testing, and 0% of 2003 revegetation efforts would pass. This analysis suggests <br />that Colowyo is in a strong position with regard to the diversity variable. <br />Contrary to the aforementioned three variables, woody plant density at Colowyo remains somewhat <br />. problematic, at least in some older areas. Perusal of Charts 6 and 7 in comparison to the current success <br />Kennecott Energy Co. / Colowyo Mine Page 5 Revegetation Monitoring - 2005 <br />