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relative proportions of species (and age or community successional status) that separates the <br />• reclaimed from the native vegetation. Perhaps the largest difference with regard to species <br />density is in the native perennial forbs category, where native areas (at least the most extensive <br />native types of Mountain Brush and Sagebrush) tend to have half again to twice as many species <br />of native perennial forbs per 100 sq.m than the four or two year old, 2004 and 2006 reclaimed <br />Areas. The seven year, 2001 Reclaimed Area, was very comparable with slightly less species <br />density of native perennial forbs than the Mountain Brush and Sagebrush Reference Areas. Data <br />for total native species density in the 2001 reclamation areas was 26.8 species per 100 sq.m. in <br />2008, up nine species per 100 sq.m. since year 2005 (17.1 species per 100 sq.m.; ESCO 2006), <br />and up nearly 13 species per 100 sq.m. since year 2003 (13.0 species per 100 sq. m.; ESCO <br />2004). Data for total native species density in the 2004 reclamation areas was 18.6 species per <br />100 sq.m. in 2008, which not even up one species since year 2006 (17.7 species per 100 sq.m.; <br />ESCO 2007). Average total species density on the 2001 and 2004 reclaimed areas exceeds that <br />of all reference areas except the Aspen reference area (Figure 4). Average total species density <br />on the 2006 reclaimed areas only exceed the Haul Road extended reference area <br />Sample Adequacy <br />A summary of sample adequacy calculations for the parameters of cover, herbaceous production, <br />and woody plant density is presented in Table 24 (Appendix 1). As can be seen in this table, the <br />• data sets for cover for two of the three reclamation areas (and the Phase II Bond release test <br />area) as well as the five sampled extended reference areas all achieved sample adequacy. The <br />data set for the 2004 reclaimed area did not achieve sample adequacy. Production data <br />collected in the Haul Road Extended Reference Area achieved sample adequacy, but all other <br />reference areas as well as the reclaimed areas data did not (Table 24). Note that no formal <br />testing for Phase III bond release that would involve herbaceous production were undertaken this <br />year, so achievement of adequacy was not at issue. As would be expected, minimum sample <br />sizes for background area shrub sampling far exceeded those taken. <br />Phase 11 Bond Release Hypothesis Testing <br />Average allowable cover observed in the Phase II bond release areas sampled in 2008 was <br />46.7%. Because it was necessary to undertake log transformation of the data from the <br />Sagebrush and Steep Mountain Brush in order to adjust asymmetry of data distribution (and <br />achieve sample adequacy) it was necessary for all data to be transformed. The mean log <br />transformed (allowable herbaceous) cover value from the Phase II Reclamation Area was 1.673. <br />This value exceeds 90% of the standard (1.510). Thus revegetation success is indicated. For <br />the information of the reader, an application of the "reverse null" hypothesis is shown as follows: <br />t= x - Q = (1.673-1.510) / (0.110/ ? 20) = 6.63 <br />• S- <br />21