Heterocyclic compounds are disclosed. Herbicidal compounds are to act in the smallest possible doses with high selectivity between useful plants and weeds. The object of the invention is to make available new chemical compounds capable of being used as herbicides. The new heterocyclic compounds have the formula (I), in which X stands for O, S, CH2 or substituted CH2 and Q stands for substituted benzols. These compounds may be provided for example in a preparation containing surface-active agents and solid or liquid diluents for controlling the growth of undesirable vegetation. Herbicidal active substances are disclosed.
