Bacillus thuringiensis serovar japonensis strain Buibui experimental formulations containing Cry8Ca1 δ-endotoxin were evaluated in the field for the control of oriental beetle, Anomala orientalis Waterhouse; Japanese beetle, Popillia japonica Newman; Asiatic garden beetle, Maladera castanea (Arrow); and European chafer, Rhizotrogus majalis (Razoumowsky) larvae infesting turfgrasses. In 17 fall applications, control of A. orientalis and P. japonica was achieved at rates as low as 100 g of toxin per ha; however, rates of 301 or 593 g/ha were consistently more effective. A. orientalis larvae were the most susceptible followed by P. japonica, R. majalis, and M. castanea. Two spring applications of 120 g of toxin per ha were not effective against oriental or Japanese beetles.