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Shrub Density • <br />Figure 3 graphically present:; shrub density totals for reclaimed areas sampled in 1994. As <br />~ can be seen, the highest densities were observed in the 1983 reclaimed area. The Wadge <br />Pasture areaalso had high densities, as has been the case in several previous years. Review of <br />1985, 1987, 1988, 1989, 15)90, 1991, 1992, 1993, and 1994 sampling data for the Seneca <br />~ II Mine shows the following documented average shrub density by year: <br />~ Sam Ig_ing Year Stems /acre <br />~ 1985 37B <br />1987 300 <br />1988 314 <br />1989 288 <br />1990 281 <br />1991 228 <br />1992 157 <br />1993 253 <br />1994 234 <br />Although these data were collected from different areas during these years, and the numbers are <br />thus not strictly comparable, the trend of decreasing, or at least not increasing, shrub density <br />through 1992 is probably real and may be related to competition from the heavy herbaceous <br />growth that comprises the high production discussed above. It may also be related to effects of <br />the on-going drought from the period of 1988 through 1990. It would appear from climatic <br />data (Figures 7 through 10), that, although the drought moderated in 1990, the period of 1991 <br />to early 1992 did not show a great increase in terms of total moisture. Since shrubs suffer in <br />competition with herbaceous plants, it is reasonable to believe that the resurgence in <br />herbaceous cover in 1991 may have had a negative effect on the density of shrubs. <br />The late 1992 and 1993 data show relatively abundant moisture for thc: first time since 1987. <br />The overall averages were "dragged down" by the very low densities obsE+rved in the youngest <br />reclamation areas in 1992, 1993, and 1994. Nonetheless, it would appear that an increase in <br />shrub density occurred between 1992 and 1993 and was sustained with only a small mortality <br />through the 1994 observations. <br />C~ <br />30 . <br />