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• HERBACEOUS PRODUCTION As with vegetation cover, herbaceous production from all areas during the 1994 growing season was less than encountered in the two prior years. In 1992, herbaceous production from the reclaimed areas totaled 62.66 g/m2 and 36.76 g/m2 from the reference area. 'fhe 1993 sampling showed herbaceous production from the reclaimed ~ - areas at 1771.7 g/m2 and 571.4 g/m2 from the reference area. Perennial grass production dominated total herbaceous production for all reclaimed areas, ranging from 93 to 99% of the total herbaceous production. Perennial grass production from the reference area was also the dominant component, totaling 88% of the total production. Annual a,~d perennial forbs, while a minor component of the total herbaceous production, were present. It is hypothesized that dry spring and early summer conditions may have precluded germination of many spring ephemeral forbs, and reduced foliage production and seed set on many perennials. Additionally, it was noted that the reference area and the 1985 and 1986 reclaimed areas had large populations of grasshoppers which may have been responsible for defoliation of succulent herbaceous forbs during the spring and early summer. • All Reclamation Areac exhibited herbaceous production above that illustrated by the iJsgoud Sand Rcieren~e Area. Based on the 1994 sampling, the 1985, i986, and 1987 Reclamation Areas would surpass the reclamation success criterion for herbaceous production. SPECIES COIViPOSTTION The Colorado Division of Minerals and Geology considers species composition of the revegetated and reclaimed areas to be an indicator of successful vegetation establishment. A standard has been set by CDMG for the evaluation of species compositiun at the Keenesburg Mine. To be judged successful, at final bond release, this standard requires that, "the species composition on the reclaimed area is such that there are at least seven perennial species of which four are warm season grasses and one is a fort. No one component of the above species should comprise greater than 40% relative importance nor less than 3% relative importance. Relative importance will be measured by calculating relative cover of the revegetation species. Vegetation species which may be used in the calculation of species composition may be any plant species not defined as a noxious or prohibited plant species, and may be native or introduced." i~ J -13-