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<br />• <br />• <br />Herbaceous production performance standard (weighted by percent of affected area) = 802 Ib/ac. <br />90 percent of performance standard = 0.9 x 802 = 722 Ib/ac <br />a Seneca IIW extended reference area values from data collected in 2007 <br />b Seneca IIW extended reference area values from data collected in 2006 <br />+ As corrected for production by annuals in excess of 10% to total production <br />As can be seen, the observed herbaceous production in the 2003 and 2005 Reclaimed Areas <br />greatly exceeded the production standard. Even the two-year old 2005 area accomplished this, <br />having had a large deduction for excess annual species. <br />Woody Plant Density <br />BACKGROUND DENSITY <br />2007 data from the 2003 Reclaimed Area indicate the average presence of 797 woody plant <br />stems per acre. In 2005 the number for woody plants was only 32 stems per acre, and thus a <br />rise of about 25x in woody plant density has occurred from the two-year old stage to the 4-year <br />old stage. This background level easily exceeds the standard of 200 stems per acre. <br />The 2005 Reclamation averaged only 53 stems per acre (Table 6) in 2007. The future is not <br />certain, but the above-referenced increase from 32 stems per acre in 2005 for the 2003 <br />Reclaimed Area to 797 stems per acre in 2007 provides encouragement that increase is possible. <br />SHRUB CONCENTRATION AREA DENSITIES <br />Tables 18 through 25 contain the data resulting from the sampling of shrub concentration areas at <br />the Seneca IIW Mine in 2007. Average shrub density values ranged from 121 stems per acre <br />(Block N) to 1214 stems per acre (Block P), but generally were below 90% of the current shrub <br />density standard (1800 stems per acre). <br />Species Diversity and Composition <br />The data illustrated in Figure 5 show that the 2005 Reclamation (the youngest) has the greatest <br />amount of annual/biennial plant cover and that the proportion of vegetation cover comprised of <br />these plants is distinctly less as reclamation age increases (i.e. 2003 Reclamation has the least <br />annual/biennial cover of the reclaimed areas). The 2003 annual/biennial cover (4-year old <br />vegetation) is about 1/3 that of the 2005 Reclamation (2-year old vegetation). Using the Figure 5 <br />illustration as typical, cover by native perennial forbs makes a substantial increase (>4x) in cover <br />over the period of maturation from age two to age four. <br />13 <br />