PROBLEM TO BE SOLVED: To provide a novel method for controlling grass weeds by soil treatment. SOLUTION: A mass ratio of a 4-HPPD-inhibiting herbicidal active substance and a photosystem II-inhibiting herbicidal active substance to the amount of the 4-HPPD-inhibiting herbicidal active substance used is used. Was 0.1 to 100, the amount of 4-HPPD-inhibiting herbicidal active substance used was 0.1 to 300 g / ha, and the amount of photosystem II inhibitory herbicidal active substance used was 100 to 2000 g / ha. Control methods for rice weeds, including soil treatment. [Selection diagram] None【課題】土壌処理による新規なイネ科雑草の防除方法の提供。【解決手段】４－ＨＰＰＤ阻害型除草活性物質と光化学系II阻害型除草活性物質とを、４－ＨＰＰＤ阻害型除草活性物質の使用量に対する光化学系II阻害型除草活性物質の使用量の質量比が０．１～１００で、４－ＨＰＰＤ阻害型除草活性物質の使用量が０．１～３００ｇ／ｈａで、且つ光化学系II阻害型除草活性物質の使用量が１００～２０００ｇ／ｈａで用いた土壌処理を行うことを含むイネ科雑草の防除方法。【選択図】なし
