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In the South Central United States, yellow bluestem (Bothriochloa ischaemum) has invaded rangelands and is known to mature earlier than native species, leading to decreased palatability and nutrition for livestock. As a result, livestock may exhibit unfavorable grazing distributions, water use, and overuse of native forage species in rangelands, thus promoting further invasion by B. ischaemum. To determine if the grazing pressure on B. ischaemum can be manipulated, thus reducing invasion, a study comparing native grasses and B. ischaemum was conducted in grazed tallgrass prairie west of Stillwater, OK on the Oklahoma State University Research Range. A total of 24 16m2 plots were established and grazing exclosure zones were placed at 12 of the plots. During the first week of June, four native grass plots and fourB. ischaemum plots were mowed. Four additional plots of both vegetation types were mowed in July. Forage nutrition, biomass, vegetation height, and soil samples were collected during the first week of August. Biomass and height results from the ungrazed plots suggest reduced grazing of B. ischaemum when it is mowed in July, however, mowing in June indicated increased grazing selection of B. ischaemum. Mowing native grasses and B. ischaemum in both June and July increased protein levels from 5% to 7% while also decreasing the number of B. ischaemum reproductive tillers. These results indicate mowing and grazing B. ischaemum in June might provide an option for range managers to control B. ischaemum invasion.