Tetrasubstituted urea compounds and herbicidal compositions

Method of combatting undesired vegetation, which method comprises applying to such vegetation or to its habitat, herbicidally effective amounts of an N,N'-tetrasubstituted urea compound of the formula ##STR200## wherein X is oxygen

• R is alkyl of from 1 to 4 carbon atoms, phenyl, benzyl or substituted phenyl or benzyl wherein the substitutent is at least one of halogen, alkyl of from 1 to 4 carbon atoms, alkoxy of from 1 to 4 carbon atoms, haloalkoxy of from 1 to 5 halo atoms, phenoxy, halophenoxy and nitrophenoxy;
• R.sup.1 is --C(Y)-R.sup.4 wherein Y is oxygen and R.sup.4 is alkyl, alkenyl, alkynyl, alkoxyalkyl, haloalkyl, haloalkynyl, cycloalkyl or cycloalkenyl of from 3 to 8 ring carbons;
• or is hydrogen or alkyl substituted by alkoxy and alkoxycarbonyl,
• R.sup.2 is alkyl, substituted alkyl, alkenyl, substituted alkynyl, wherein the substituents are at least one of alkoxy of from one to three carbon atoms, haloalkyl of from one to two carbon atoms and one to three halogen atoms, and halogen, alkoxy or cycloalkyl of from 3 to 8 carbon atoms;
• R.sup.3 is alkyl, haloalkyl or alkenyl or up to 4 carbon atoms;
• R.sup.2 and R.sup.3 represent an alkylene bridge.