In Vitro: Benzobicyclon (100-300 g a.i./ha; 1 L or 2 L) exhibits excellent herbicidal activity against S. juncoides regardless of the emergence depth between 0 and 3 cm and (200-300 g a.i./ha; pre-emergence; 1 L) hardly affected by the soil types. Benzobicyclon (300 g a.i./ha; 1-leaf and 1 L stages) completely controls S. juncoides at 25°C, 20°C, and 15°C, and takes longer to reach 90% control at low temperatures. Benzobicyclon (200, 300 g a.i./ha; pre-emergence and 1 L stages) exhibits excellent herbicidal activity against all SU-R biotypes S. juncoides, M. vaginalis and L. dubia as well as SU-S biotypes. (SU-S: sulfonylurea herbicide-susceptible, SU-R: sulfonylurea herbicide-resistant). Benzobicyclon (200-600 g a.i./ha; pre-emergence and 1 L stages) exhibits excellent herbicidal activity against E. crus-galli , S. juncoides, M. vaginalis, L. var. dubia and C. serotinus and shows good rice crop safety.