One hand weeding supplemented with thiozypyr at 120 or 150 g ha·1 being statistically at par with two hand weedings (20 and 40 DAS) reduced the dry weight of weeds to the extent of 90% and resulted in seed yield of mustard statistically equivalent to weed-free plots. Chlorimuron caused 92-98% crop injury. Weeds growing throughout the crop season resulted in 24.7% reduction in seed yield of mustard.