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Old World Bluestems (Dichanthium annulatum and Bothriochloa ischaemum; OWB) are classified as invasive plant species that are encroaching native rangelands in Texas, especially in the south Texas region. Historically, OWB were planted for grazing on rangelands and erosion control along roadsides; however, they provide poor quality wildlife habitat and livestock forage. Currently, no individual control method has proven to effectively manage OWB. Therefore, the objective of this study was to evaluate combinations of treatment methods in triplicate plots to manage these invasive grasses. We used primary (summer fire, glyphosate, or nicosulfuron + metasulfuron methyl, and control) followed by secondary treatments (plowing, mowing, plowing + reseeding with a native mixture, or fertilizer, and a control) in a factorial design (4 ? 5) to integrate multiple management practices and determine the most effective treatment combination. The experiment was conducted at three different sites, in two counties, representing different soil types and climatic conditions in south Texas. Cover and botanical composition of plots and yield of OWB were estimated bimonthly over 2 years to determine which treatment combinations were the most effective. Cover was initially decreased by treatments, but after 16 mo only primary treatments followed by plowing, mowing, or plowing + seeding with a native mixture had decreased (P < 0.05) cover. After 16 mo, total herbage mass (kg ha-1) and OWB (% of cover) declined (P < 0.05) with primary treatments followed by plowing or plowing + reseeding. After 16 months of observation, OWB is best controlled with these primary treatments followed by plowing. Alternative management practices which control OWB without destroying other native plant species are necessary.