Among those chemicals were DDT, banned by international convention, and several defoliants and herbicides. Defoliants are widely used for the selective removal of weeds in managing croplands and lawns. Defoliants eroded tree cover and seedling forest stock, making reforestation difficult in numerous areas. Common harvest-aiding chemical defoliants include tribufos, dimethipin, and thidiazuron. Defoliants are used to quickly kill vegetation and deny its use for cover and concealment. The use of defoliants aids in the effective harvesting of cotton and finer lint quality. The Defoliants at his Attica Studios in Chicago, Illinois. In this operation, the unit applied two treatments to the target areas with defoliants. A primary application of defoliants is the selective killing of plants.