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Countering these decreases was an increase in introduced perennial fortis (mostly cicer <br />milkvetch) from 7 percent of total vegetation cover in 2000 to 20 percent in 2003. <br />Also increasing from 2000 to 2003 was cover by introduced annual grasses (from 1 percent of <br />total vegetation cover) to 5 percent of total vegetation cover. It is thought that the latter increase <br />in annual brome presence was probably the vestige of high late summer precipitation in 2000 and <br />2001 which would be expected to have encouraged heavy growth by these winter annuals. <br />Winter annual species like Japanese brome and cheatgrass are strongly boosted by late summer <br />moisture that allows them to germinate prior to winter. <br />1999 reclamation at the Seneca II-W Mine was last monitored in 2001 (see ESCO 2002), a year <br />that was somewhat drier than 2003 (Figures 6a, 6b, 7a, 7b, 8a, 8b). In the intervening two years, <br />the abundance of annual species typical of young reclamation was reduced from 66 percent of <br />total vegetation cover to 27 percent of total vegetation cover. Native perennial forb cover rose <br />from 3.8 percent of total vegetation cover to 11 percent of total vegetation cover. Native <br />perennial cool season grass cover increased from 25 percent of total vegetation cover to 37 <br />percent. Cover by introduced perennial cool season grasses also increased. Cover by shrubs <br />increased from immeasurably low in 2000 to 0.8 percent of total vegetation cover in 2003. <br />Herbaceous Production <br />. Observed production values and derivation of the 2003 herbaceous production standard are <br />compiled /documented in the table below: <br />Seneca II-W 2003 <br /> <br />Phase III Herbaceous Production Standard <br />Vegetation Type Mean Herbaceous Production (Ib/ac) % of Aff. Area <br />Sagebrush/Snowberrya 1768.3 38.0 <br />Mountain Brush° 1589.9 37.3 <br />Aspen Woodland° 2234.0 7.0 <br />Steep Mountain Brush 748 13.9 <br />Alkali Sage/West Whtgrs. 1,411 3.8 <br />1996 Reclamation Area 2535.6 NA <br />1999 Reclamation Area 2301.9 NA <br />Herbaceous production performance standard (weighted by percent of affected area) = 1579 Ib/ac. <br />90 percent of performance standard = 0.9 x 1579 =1421 Ib/ac <br />11 <br />