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Switchgrass (Panicum virgatum) can produce biomass on marginal ground that can be used as biofuel feedstock. In the Southern Plains, marginal ground is often in established bermudagrass (Cynodon dactylon). To convert bermudagrass to nativegrass, methods are needed for suppression or control of bermudagrass, allowing opportunity for nativegrass establishment. A two-year study was developed to evaluate twelve treatments for bermudagrass suppression prior to establishment of switchgrass (‘Alamo') or a mixture of little bluestem (Schizachyrium acoparium ‘Cimarron'), big bluestem (Andropogon gerardii ‘Kaw'), indiangrass (Sorghastrum nutans ‘common'), switchgrass (‘Alamo'), and green sprangletop (Leptochloa dubia ‘common'). Treatments were six no-till and six clean-till planting methods, each with or without a winter cover crop of cereal rye (Secale cereale ‘Maton II') and summer cover crop of sorghum sudan (Andropogon bicolor ‘Sweet Sunny Sue') with combinations of glyphosate and preparation time (7 to 19 months prior to planting) across two locations. The first year of the study began in the fall of 2009 and planting date for all treatments was April, 2011. Stand counts were taken in June 2011. First year harvest date was March 2013. Year two was planted in April 2012. Only first year study data is presented. Switchgrass and nativegrass stand counts across locations established by no-till averaged 20% and 11% compared to clean-till averages of 76% and 41%. On a fine sandy loam soil location, mean treatment yield of clean-till established switchgrass (8187 kg ha-1) was greater than (P < 0.05) no-till (3166 kg ha-1). Clean-till had no effect on switchgrass yield on loamy fine sand location. Clean-till improved nativegrass yields at both locations (P < 0.05). Across locations, weeds composed 29.5% of switchgrass and 72.5% of nativegrass total biomass. Based on first year results, establishment methods with tillage are superior to no-till establishment.