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Effects of Grazing in the Wadce Pasture Unil As of the 1991 sampling, it had been tour years since grazing began in the Wadge Pasture. As mentioned in the 1990 Revegetation Monitoring Report, there had been a decline in cover and production over the entire study area including reference areas during the period of 1987 to 1989, followed by a modest rebound in 1990. In 1991, cover rebounded further as it did in all reclaimed areas, but whereas the overall reclaimed area cover increased by slightly over 5 percent cover, the Wadge Pasture cover rose by slightly over 13 percent cover. Thus the trend of this grazed ., area, as cited in earlier Seneca II Revegetation Monitoring Reports, to have cover values higher than ungrazed areas, both in times of overall increase as well as in times of general decrease, continues in 1991. In 1991, as in 1990, production levels in the Wadge Pasture were higher than in any other reclaimed area sampled at the Seneca II Mine, except the 1990 sampling of the 1986 Wadge Spring area where an extreme development of alfalfa accompanied an extremely high level of production. It is of interest that while cover rose by about 20 percent between 1990 and 1991, herbaceous production increased by less than 5 percent. This trend was generally observable throughout the reclamation, and might be explained by an expansion of perennial grasses by tillers and rhizomes info areas left open from the drought. The above-ground shoots from such widespread tillers or rhizomes are not likely to have much biomass initially, so relatively little effect would be shown in production while ground cover increased more noticeably. Another (or an additional) possible explanation suggested by the climatic data (see below) is that the relatively dry months of April and May retarded the growth of grasses so that shoots from new tillers or rhizomes were still relatively small by early July during the sampling period. Whereas, speculation in the 1989 Revegetation Monitoring Report on the cause of the resilience of the production (and cover) of the Wadge Pasture centered on the release of nutrients bound in accumulated litter, the tact that the Wadge Pasture Comparison area (ungrazed) sampled in 1990 compared so closely with the Wadge Pasture in cover and production cast doubt on the likelihood that grazing effects had been so dramatic as earlier supposed. The extra-high cover in the Wadge Pasture in 1991 compared to other reclaimed areas again raises the question of the cause of this difference. Since the 'Wadge Pasture Comparison Area' sampled in 1990 and carefully circumscribed to match the Wadge Pasture in every way except the presence of grazing, was not sampled in 1991, rio direct proof of the effects of grazing in the above referenced cover increase in Wadge Pasture is available. r, U 19