Grazing reclaimed mined land seeded to native grasses in Wyoming

ABSTRACT:

Methods mandated for evaluating mined-land reclamation success often involve comparisons of vegetative cover, species diversity, and productivity between reclaimed lands and undisturbed reference areas. An alternative utilitarian approach, used in this study, addresses the capability of reclaimed land to properly function and sustain its intended post-mining use. A 5-year grazing study was conducted to evaluate the success of reclamation on uranium-mined land in Wyoming. Stocking rates of 0.25 and 0.5 steers ha⁻¹ were replicated on 12 ha pastures to evaluate the effect of grazing on the vegetative community and animal response. Forage production and plant community composition of the pastures were not affected by stocking rate. However, the percentage of bare ground decreased 43% and litter cover increased 82 % under both stocking rates. Native perennial grasses in the plant community increased 110%. Yearling steer gains were significantly greater on the low stocking rate, averaging 0.94 kg day⁻¹ for the 0.25-steers-ha⁻¹ and 0.81 kg day⁻¹ for the 0.50-steers-ha⁻¹ stocking rate. The increase in perennial native grasses and litter cover and the decrease in bare ground demonstrate that the ecosystem was not harmed and my have been improved by grazing.