IMPACTS OF ROTATIONAL GRAZING ON MIXED PRAIRIE SOILS AND VEGETATION

In this study the impact of a rotation grazing system on the soil and vegetation of a Stipa-Bouteloua-Agropyron community in the mixed prair ie ecoregion was compared with the ungrazed treat ment in exclosures. At a low stocking rate, grazing had no effect on the vegetation but di d alter soil quality. Grazing pressure was so light in the rotational grazing treatment that recovery of productivity, as measured by standi ng crop and litter, was not significantly different from the ungrazed treatment. Conversely, the species distribution was unchanged but was indicative of a lower seral state for this mixed prairie. The effect o f grazing on this community was indirect, possibly by altering the mic roenvironment, The relationships observed among forage production, soi l chemistry, and species composition raise questions on the importance of any one variable expressing range condition on the mixed prairie.