Herbicides containing a pyrazole derivative of the formula ##STR1## where R.sup.1 denotes hydrogen, formyl, acetyl, propionyl, chloroacetyl, dichloroacetyl, methoxyacetyl, methoxycarbonyl, or phenoxycarbonyl which is unsubstituted or mono- or polysubstituted by halogen, R.sup.2 denotes phenyl which is unsubstituted or mono- or polysubstituted by fluorine, chlorine, bromine, methyl, methoxy, cyano, nitro, trifluoromethyl, trifluoromethoxy or methoxycarbonyl, R.sup.2 further denotes a 5- to 6-membered, heterocyclic aromatic ring which is unsubstituted or substituted by methyl or chlorine and which contains 1 or 2 hetero-atoms X, X being independently oxygen, sulfur or nitrogen, or R.sup.2 denotes .alpha.-naphthyl or .beta.-naphthyl, and R.sup.3 denotes methyl, ethyl or isopropyl, or a salt of such a pyrazole derivative, a process for combating unwanted plant growth with the active ingredients and methods of manufacturing the herbicides.