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HERBACEOUS PRODUCTION • As with vegetation cover, total herbaceous production was quite variable during the 2001 growing season (Table I1). Mean herbaceous production ranged from 119.71 g/mZ (Osgood sand reference azea) to 242.71 g/mZ (1997 reclamation areas). All azeas showed an increase in herbaceous production over 2000 production values, ranging from 78.5 percent (1998 reseeded or interseeded areas) to 176.1 percent in the 1997 reclamation azeas. Perennial grasses dominated total herbaceous production in all azeas sampled this year accounting for between 57.2 percent and 81.8 percent of the total herbaceous production. Annual grasses contributed significantly to herbaceous production this yeaz, lazgely due to the rapid early season growth of Bromus teciorum. Annual and perennial forts contributed significantly also this yeaz, with total production of all forts ranging from 9.1 percent in the 1995 reclamation areas to 30.1 percent in the 1997 reclamation areas. Fort growth was aided by the early and persistent precipitation during the 2001 Bowing season. SPECIES COMPOSITION The Colorado Division of Mmerals and Geology considers species composition of the revegetated and reclaimed areas to be an indicator of successful vegetation establishment and a diverse vegetation community. A standard has been set by CDMG for the evaluation of species composition at the Keenesburg Mine. To be judged successful, at • final bond release, this standazd requires that, "the species composition on the reclaimed azea is such that there aze 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." A comparison of the 2001 species composition data with the revegetation success standard reveals that only the 1995 reclamation areas meet the final bond release species composition success standazd. The Osgood sand reference area lacks a perennial fort and the required number of species with qualifying relative cover values. The 1997 reclamation areas and the 1998 reseeded or interseeded azeas lack the required number of warm season grasses. Species presence and representation on the reference and reclaimed azeas was greater than encourttered in 2000, attributable to increased precipitation (Tables 1,12). The Osgood sand reference area contained ten more species in 2001 than in 2000, the 1995 and 1997 reclamation azeas contained four and fourteen more species respectively, and the 1998 reseeded or interseeded areas increased in species numbers from seventeen in 2000 to twenty-three this year. • -18-