2009-04-01_REPORT - C1982057 (6)

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• *Percent "all-hit" cover (absolute) by herbaceous species as corrected for "allowable" annual and biennial cover (i.e. no more than 10 percent relative cover allowed, See CDMG 1995, 1.IV.A.). Cover by noxious weed species, if any, also subtracted. a Seneca IIW extended reference area values from data collected in 2008 b Seneca IIW extended reference area values from data collected in 2006 As can be seen in Figure 1a, the mean allowable total "all hit" herbaceous cover observed in the four-year old 2004 Reclaimed Area was slightly below the 90 percent of the standard set by the reference areas. The very young (two-year old) 2006 and (one-year old) 2007 Reclamation fell well short of the standard of allowable cover. In 2006 when the two-year old (then) 2004 Reclamation was sampled, the allowable cover was 12.3% in the reclaimed and 90% of the standard was 26.2%. This pattern has been observed previously; two-year old revegetation is still developing and hence a situation in which the allowable cover of two-year old reclamation does not reach 90% of the Phase III standard is not necessarily indicative of a problem. Another reason for none of the reclamation areas meeting the standard of allowable cover could be attributed to the large numbers of grasshoppers and their heavy grazing on the reclamation vegetation observed in 2008. In as much as the 2004 Reclaimed Areas at the Seneca IIW Mine were also sampled in 2006, a • year that was below average in moisture, it is interesting to observe the changes in cover valuers between 2006 and 2008. 2008 was a year that was much above average in moisture for the previous twelve months (Figures 6b, 7a and 8b) but well below average in the period of the previous four to six months (Figures 8b and 9b). Total cover by annuals fell between 2006 and 2008 from 19% to 16%. Native perennial forbs nearly doubled in cover over the period and native perennial cool season grass cover slightly rose as well. Shrub cover rose from immeasurably low in 2006 to 0.2% in 2008. Overall cover by introduced perennial cool season grasses rose by more than four times from 0.6% in 2006 to 2.7% in 2008, with a large increase in intermediate wheatgrass. Total species density fell from 30.4 species per 100 sq.m. in 2006 to 28.2 species per 100 sq.m. in 2008 which was largely due to the disappearance of a few introduced annual/biennial forbs. Herbaceous Production E Observed production values and derivation of the 2008 herbaceous production standard are compiled / documented in the table below: Seneca IIW 2008 Vegetation Type Mean Herbaceous Production (Ib/ac) k % of Affected Area 13