Defoliant

A defoliant is any chemical sprayed or dusted on plants to cause its leaves to fall off.

A classic example of a highly toxic defoliant is Agent Orange, which the British military used abundantly to defoliate regions of Malaya starting in the early 1950s during the Malayan Emergency of 1948–60, and the U.S. military to defoliate regions of Vietnam from 1961 to 1971 during the Vietnam War of 1955–75.

Defoliants differ from herbicides in that the former seeks mainly to strip leaves from plants, and the latter is used to destroy or inhibit the growth of certain plants.

Defoliants are used in cotton production to aid harvesting.

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