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• Species Composition Cover sampling identified two lif'eforms and fourteen species within the 1998 reseeded or interseeded areas. The lifeforms included seven species of perennial grass, one annual grass, one perennial, one biennial, and four annual forbs. Of the species encountered on the 1998 reseeded or interseeded aeeas, nine were native and five were introduced. Perennial species outnumbered annual species by eight to five, with one biennial. Both warm and cool season species contributed to the seasonality of the 1998 reseeded or interseeded areas. Graminoids were evenly split between warm and cool season species. Five forb species were identified as cool season and one was warm season. The 1998 reseeded or interseeded aeeas had six species contributing greater than three percent relative cover this year. The species contributing greater than three percent relative cover included two perennial grasses, one annual grass, and three annual forbs. These species included Bromus tectorum (58.39%), Bouteloua gracilis (10.74%), Calamovilfa longijolia (10.07%), felianthus annuus (5.37%), Kochia scoparia (5.37%), and Sisymbrium altissimum (3.36%). QUALITATIVE EVALUATION: 1985, 1986, AND 1987 RECLAMATION AREAS 1985 RECLAMATION AREA • The 1985 reclamation area encompasses approximately 23 acres of reclaimed pit in the north central area of the Keenesburg Mine permit area. The 1985 reclamation area is composed of two parcels (west and east) separated by a north-south haul road corridor, This area is nearly flat with a gentle slope (Q°) to the north and east. Reclamation and coincident revegetation within this area took place in 1985. Replaced soils were sandy in texture. The revegetation seed mix differed slightly in composition and representation of cool season grasses from the seed mix applied to the 1986 and 1987 reclaimed areas, yielding a slightly different species composition. Vegetation growth in both 1985 reclamation area parcels was very good this year. Visually dominant species included Andropogon hallii, Bromus marginatus, Calamovilja longifolia, Ambrosia psilostachya, and Helianthus annuus. Additional contributors observed included Agropyron cristatum, Panicum virgatum (switchgrass), and widely scattered individuals of Opuntia polyacantha (prickly pear), Artemisia frlifolia, and Yucca glouca (yucca). Total mean vegetation cover was estimated between 55 and 65 percent. Herbaceous production of this area was estimated at 170 g/mZ (1515 Ib/ac). Species numbers appeared equivalent to past years, and there was no evidence of invasion by unwanted species or evidence of pest or disease problems. _12_