Vegetation and Animal Production from Reclaimed Mined Land Pastures
Limited data are available on the productivity and persistence of reclaimed mined land in the northern Great Plains used for grazing. The purpose of this study was to compare standing crop, vegetation use, steer (Bos spp.) performance, soil compaction, and measurement methods on reclaimed cool-season pasture near Center, ND, at three grazing intensities and grazed each spring over 5 yr. Light and moderate intensity pastures were grazed an average of 36 days, with an average total vegetation use of 35 and 47%, respectively. Heavy intensity pastures were grazed 27 days and averaged 93% use. Live vegetation production averaged 2040,2860,2390, and 1630 kg ha−1 dry matter in early July for ungrazed exclosures and light, moderate, and heavy intensities, respectively, over the 5 yr; litter averaged 1440, 1180,640, and 200 kg ha−1, respectively. Yearling steers gained an average of 64,86, and 31 kg ha−1 and 1.2, 1.0, and 0.3 kg day−1 at the light, moderate, and heavy intensities, respectively. The heavy intensity was detrimental to both vegetation and livestock production, but vegetation dry matter and liveweight gain improved when grazing was moderated in 1981. Grazing did not measurably affect soil bulk density in the top 150 mm of soil, but proving ring penetrometer measurements indicated increased soil compaction with increased grazing intensity. With 50% or less total vegetation removal in early summer, the reclaimed grassland provided sustained productive post-mine grazing use with no signs of deterioration.
Copyright © . .