Pyridine-2,3-dicarboximides of the general formula I ##STR1## where R.sup.1 is hydrogen, alkoxy or unsubstituted or substituted alkyl, cycloalkyl, alkenyl or alkynyl and R.sup.2, R.sup.3 and R.sup.4 are identical or different and are each hydrogen, halogen, cyano, unsubstituted or substituted alkyl, benzyl, cycloalkyl, alkenyl, alkynyl, alkoxy, phenoxy or phenylthio, a 5-membered or 6-membered heterocyclic radical having one or two hetero atoms selected from the group consisting of oxygen, sulfur and nitrogen, or unsubstituted or substituted phenyl, with the proviso that a) R.sup.2 is fluorine and R.sup.3 and R.sup.4 have the abovementioned general meanings or b) R.sup.3 is fluorine, chlorine, C.sub.1 -C.sub.3 -alkoxy, C.sub.2 -C.sub.5 -alkenyloxy, C.sub.2 -C.sub.5 -alkynyloxy, trifluoromathyl or cyano and R.sup.2 and R.sup.4 have the abovementioned general meanings or c) R.sup.4 is halogen or C.sub.1 -C.sub.3 -alkoxy, C.sub.2 -C.sub.5 -alkenyloxy or C.sub.2 -C.sub.5 alky-nyloxy and R.sup.2 and R.sup.3 have the abovementioned general meanings, with the exception of 5-chloropyridine-2,3-dicarboximide, and the environmentally compatible salts thereof.