Hydroximic acid halides of the formula I ##STR1## where the substituents have the following meanings: X is NOCH.sub.3, CHOCH.sub.3 or CHCH.sub.3 ; Y is O or NH; R.sup.1 is halogen; R.sup.2 is unsubstituted or substituted alkyl, alkenyl, alkynyl, cycloalkyl or aryl; R.sup.3 is unsubstituted or substituted alkyl, alkoxyalkyl, cycloalkyl-alkyl, alkenyl and alkynyl, their salts, processes for their preparation, and their use.