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In 1993, herbaceous production levels in the Wadge Pasture were higher than in any other • <br />reclaimed area sampled by E:SCO between 1987 and 1993 at the Seneca II Mine. It is of interest <br />that while cover rose by about 20 percent between 1990 and 1991, herbaceous production <br />increased by less than 5 percent. Between 1991 and 1992, cover fell by about 7 percent while <br />herbaceous production rose by 10 percent. Between 1992 and 1993, cover increased by about <br />6 percent and herbaceous production rose by 13 percent. In 1994, cover tell by about 21 <br />percent, while herbaceous production decreased by 24 percent. The severely dry conditions of <br />1994 were obvious in the substantial decreases in both cover and herbaceous production. In <br />1995, cover rose by 28 percent and herbaceous production rose by 68 percent. 1996 data <br />showed cover down by 11 percent and herbaceous production down by 2Ei percent. Dominance <br />by introduced species would seem to be associated with higher volatility in both cover and <br />herbaceous production. <br />Despite the volatility in cover and herbaceous production between years, after nine years of <br />grazing treatment, the Wadge Pasture area seems to have had few if any ill-effects attributable <br />to grazing, and in fact exceeds most other reclaimed areas in the performance standards of <br />vegetation cover, herbaceous production, and shrub density. <br />Over the period of 1988 to 1992, the Wadge Pasture had a consistent introduced species density <br />of about 9 species per 100 sq. m.; in 1993 that rose to 11 species per 100 sq. m., remained at <br />that level in 1994, and increased slightly to 11.5 species per 100 sq. m. in 1995, and rose <br />further to 13.0 species per 100 sq. m. in 1996. Native species density has increased between <br />1988 and 1992 from about 10 species per 100 sq. m. to about 12 species per 100 sq. m.; in <br />1993, it rose to 16 species per 100 sq. m. and remained at that level in 1994; 1995 native <br />species density fell to 14.1 species per 100 sq. m. in the face of very heavy competition from <br />introduced species; it declined further to 13.8 species per 100 sq. m. iri 1996. Thus, although <br />the trend over the past two years is negative, the overall effect of grazing over the past nine <br />years has corresponded with a 50 percent increase in average native species diversity, as <br />reflected by species density data. <br />Sample Adequacy <br />A summary of sample adequacy calculations for the parameters of cover, herbaceous production <br />and woody plant stem density is presented in Table 21 (Appendix 1). A:; can be seen in Table <br />• <br />30 <br />