A description is given of 4-trifluoromethylpyrazolyl-substituted pyridines and pyrimidines of formula (I) and of their use as herbicides. ##STR00001## In this formula (I) R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are various radicals, A is an aromatic or heteroaromatic radical, and Z is a nitrogen or carbon atom.