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the earliest monitoring (2004) at which time the total was 1392 stemsfac, most of which was big sagebrush. In the intervening two years there has been a winnowing away of about half of the sagebrush perhaps as a result of competition. In the 2004 reclaimed area, the start for woody plant density is slow, with only 48 stems/ac. 2004 was anear-average year for moisture and may have seen too much competition for young shrub seedlings to tolerate. SHRUB CONCENTRATION AREA DENSITIES Tables 27 through 39 contain the data resulting from the sampling of shrub concentration areas at the Seneca IIW Mine in 2006. Average shrub density values ranged from 49 stems per acre (Block I) to 8984 stems per acre (Block J), but generally were below 90% of the current shrub density standard (1800 stems per acre). Species Diversity and Composition The data illustrated in Figure 5 show that the 2004 reclamation (the youngest) has the greatest amount ofannual/biennial plant cover and that the proportion of vegetation cover comprised of these plants is distinctly less as reclamation age increases (i.e. 1999 reclamation has the least annual/biennial cover of all the reclaimed areas). The 1999 annual/biennial cover (7-year old vegetation) is about'/, that of the 2004 reclamation (2-year old vegetation). Using the Figure 5 illustration as typical, cover by native perennial forbs makes a substantial increase in cover over the period of maturation from two to seven years old. The distribution of species density by lifeform (Figure 4) shows that the 1999, 2002 and 2004 reclaimed areas are more similar to the reference areas than would appear to be the case from the lifeform distribution of relative cover (Figure 5). This is important in that it shows that the basic components of the original ecosystem have indeed been returned and that it is a matter of relative proportions and successional status that separates the reclaimed from the native vegetation. Perhaps the largest difference with regard to species density is in the native perennial forbs category, where native areas (at least the most extensive native types of Mountain Brush and Sagebrush) tend to have half again to twice as many species of native perennial forbs per 100 sq.m. 2006 data for total native species density in the 1999 reclamation areas was 22.8 species per 100 sq.m. in 2006, up more than 10 species per 100 sq.m. since year 2000 (12.1 species per 100 sq.m.; ESCO 2002). Average total species density on the reclaimed areas exceeds that of all reference areas except aspen (Figure 4). Sample Adequacy A summary of sample adequacy calculations for the parameters of cover, herbaceous production, and woody plant density is presented in Table 25 (Appendix 1). As can be seen in this table, the 18