2008-03-27_REPORT - C1994082 (5)

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predominance of perennial desirable species. It should be noted that during the 2005 monitoring, • the 2003 reclamation, then only two years old, likewise failed to meet the standard. As of 2007, and the passage of two more years of development, the allowable cover does pass (Figure 1 a). Thus, it seems likely that the 2005 reclamation while not yet meeting the cover standard will progress in the next few years and eventually meet the standard, well before the end of the liability period. • • Inasmuch as the 2003 reclaimed areas at the Yoast Mine were also sampled in 2005, a year that was above average in moisture, it is.interesting to observe the changes in cover values between 2005 and 2007, which was a year that was below average in moisture (Figures 6b, 7b and 8b). Despite drier conditions in 2007, total cover went up even though cover by annual /biennial species fell by half. This was mostly due to increases in perennial forb cover (Western yarrow, blue flax, Rocky Mountain penstemon, Cicer milkvetch, and alfalfa) and two perennial grasses, orchardgrass and common timothy. Herbaceous Production Observed production values and derivation of the 2007 herbaceous production standard are compiled /documented in the table below: Yoast 2007 Vegetation Type Mean Herbaceous Production (Ib/ac)* % of Affected Area Sagebrush/Snowberrya 1053 24.0 Mountain Brushy 998 48.9 Aspen Woodland 764 24.4 Steep Mountain Brush 473 2.7 2003 Reclamation Area 1176 NA 2005 Reclamation Area 642 NA Herbaceous production performance standard (weighted by percent of affected area) = 940 Ib/ac. 90 percent of performance standard = 0.9 x 940 = 846 Ib/ac a Yoast extended reference area values from data collected in 2007 b Yoast extended reference area values from data collected in 2006 As corrected for "allowable" annual and biennial production (i.e., no more than 10 percent of total production allowed, See CDMG 1995, 1.IV.A.) Production by noxious weed species, if any, also subtracted. 12