FIELD: chemistry.
SUBSTANCE: synergistic herbicidal composition comprising a herbicidally effective amount of (a) a compound of formula 
or agriculturally acceptable salt or ester thereof and (b) at least, one compound or agriculturally acceptable salt, carboxylic acid, carboxylate salt or ester selected from the group consisting of atrazine, bentazone, bentazone-sodium, bromoxynil, cyanazine, diuron, hexazinone, ioxynil, isoproturon, linuron, methibenzuron, metribuzin, propanil, simazine, simetrin, tebutyuron and terb tilazin, wherein (a) and (b) are present in the combination in such a ratio, wherein the combination exhibits synergism, and wherein the ratio (a):(b) ranges from about 1:2 to about 1:560.
EFFECT: increasing the effectiveness of controlling unwanted vegetation.
40 cl, 33 tbl, 5 ex
