Wild oat herbicide mixture

A herbicidal composition comprising as active ingredient an N,N-disubstituted alanine derivative having the following general formula:

• ##STR6## wherein Y and Z each represent, fluorine or chlorine, X is oxygen or sulfur;
• and R is hydrogen or an alkyl group containing up to 6 carbon atoms;
• and as a synergist therefor, a methylenedioxybenzene derivative having the following general formula:
• ##STR7## wherein X' is a polyglycol ether group containing up to 20 carbon atoms and 2 to 6 oxygen-ether linkages and Y' is hydrogen or an alkyl group containing up to 6 carbon atoms, said alanine derivative and methylenedioxybenzene derivative being present at a weight ratio of the alanine derivative to the methylenedioxybenzene derivative of from 10:1 to 1:10.