Spinosad, a commercial bacterial insecticide, was evaluated on three Kansas farms. On each farm, spinosad applied at 1 mg(AI)/kg to hard red winter wheat was compared with wheat receiving 3 mg(AI)/kg of chlorpyrifos-methyl (Reldan), 1 mg/kg spinoad + 3 mg/kg chlorpyrifos-methyl, and untreated wheat. Wheat was sampled monthly soon after treatment in July 2002 and continued until January 2003 to determine number of live insects, persistence of spinosad residues, and grain quality parameters. Very few or no live insects were found in wheat receiving spinosad or spinosad + chlorpyrifos-methyl. Wheat receiving chlorpyrifos-methyl had live insects two months after treatment, and most of the insects were lesser grain borers. Spinosad residues were stable during the six month study period. Spinosad appears to be a viable stored grain protectant.