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Bothriochloa ischaemum (yellow bluestem) is an introduced Old World bluestem commonly planted to Conservation Reserve Program fields or as an alternative livestock hay or forage throughout the southern Great Plains. Research indicates B. ischaemum provides minimal ecosystem services in invaded rangelands. In an effort to reduce B. ischaemum invasion, we implemented a grazing study comparing mowed and non-mowed B. ischaemum and native forages to determine livestock preference of the forages. Three invaded rangeland sites were located at the Stillwater Research Range near Stillwater, OK, USA. At each site 12 B. ischaemum and 12 native forage plots were established; each plot consisted of an exclosure and an open block (4m2 each) to compare the mowing and grazing treatments. In June 2015 leaf length, inflorescence density, and biomass were measured prior to mowing. We then randomly mowed six B. ischaemum and six native forage plots at each site to a height of 5cm. In July, August, and September, leaf length and inflorescence density were measured, and biomass was measured again only in September. Preliminary results suggest grazing with or without mowing reduced leaf length of B. ischaemum proportionally more than the native forage. Grazing with mowing reduced inflorescence density by 37%-77%, whereas grazing without mowing reduced density by 16%-72%. Native forages had minimal reduction in inflorescence density. Biomass has been collected and results will be presented. These results indicate mowing and grazing may an affordable tool in reducing B. ischaemum invasion without hindering native forage production.