A description is given of 4-trifluoromethylpyrazolyl-substituted pyridines and pyrimidines of the 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 stand for various radicals, A for an aromatic or heteroaromatic radical, and Z denotes a nitrogen or carbon atom.