Abstract: Use of 2-chloro-3-(methylsulfanyl)-N-(1-methyl-1H-tetrazol-5-yl)-4-(trifluoromethyl)benzamide or its salts for controlling unwanted plants in areas of transgenic crop plants being tolerant to HPPD inhibitor herbicides. The use of 2-chloro-3-(methylsulfanyl)-N-(1-methyl-1H-tetrazol-5-yl)-4-(trifluoromethyl)benzamide or its salts for controlling unwanted plants in areas of transgenic crop plants being tolerant to HPPD inhibitor herbicides by containing one or more chimeric gene(s) comprising (I) a DNA sequence encoding hydroxyphenylpyruvate dioxygenase (HPPD) derived from a member of a group of organisms consisting of (a) Avena, (b) Pseudomonas, (c) Synechococcoideae, (d) Blepharismidae, (e) Rhodococcus, (f) Picrophilaceae, (g) Kordia, or (II) one or more mutated DNA sequences of HPPD encoding genes of the before defined organisms, preferably from Pseudomonas, or (III) one or more DNA sequences encoding mutated maize (Zea mays) or soybean (Glycine max) HPPD each being mutated as described in WO 2012/021785.