Applying a spray or dust to plants to cause their leaves to drop off prematurely. Defoliants are sometimes used on crop plants like cotton to facilitate harvesting. In warfare, defoliants are used to eliminate food crops and potential areas of concealment.
Defoliants were used extensively by American and South Vietnamese forces in the Vietnam War.
The use of defoliants has not proved to be effective except as a certain harassment value.
The use of defoliants has caused long-term damage to ecology and to humans and will require massive corrective measures.