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" Seneca II-WS extended reference area values from data collected in 1997 As can be seen in Figure 1, the allowable total "all hit" herbaceous cover observed in the 1995 reclaimed areas sampled exceeded 90 percent of the standard set by the reference areas. Inasmuch as the 1995 reclaimed areas at the Seneca II-W Mine were also sampled in 2001, a year that was only slightly drier than average, it is interesting to observe the changes in cover values between 2001 and 2002 (see ESCO 2002). Total vegetation cover was insignificantly different between the two years, but components of the vegetation cover did experience changes. Cover by native perennial cool season grasses declined from 48.1 percent of total vegetation cover to 36.2 percent of total vegetation cover. Cover by introduced annual and biennial forbs dropped from 13.4 to 8.4 percent of total vegetation cover. Introduced perennial forbs (mostly alfalfa and cicer milkvetch) dropped from 12.3 percent of total vegetation cover in 2001 to 1.3 percent in 2002. Countering these decreases was an increase in cover by native perennial forbs from 10.7 percent of total vegetation cover to 15.7 percent of total vegetation cover. Also increasing from 2001 to 2002 was cover by introduced annual grasses (from 2.7 percent of total vegetation cover) to 24.5 percent of total vegetation cover. The latter dramatic change was probably triggered by the occurrence of over twice the average precipitation in August 2001. Winter annual species like Japanese brome and cheatgrass are strongly boosted by late summer moisture that allows them to germinate prior to winter. Most of the increase in cover by native perennial forbs was attributable to increase by blue flax which may also have germinated in fall 2001 and flowered immediately, as it has the capability of doing: Herbaceous Production Observed production values and derivation of the 2002 herbaceous production standard are compiled /documented in the table below: