2,4-Dichlorophenoxyacetic acid is a low volatile, white odourless solid from the auxin and carboxylic acid groups. It was used on a massive scale by the US military in the 1960s as a component of the defoliant Agent Orange in the Vietnam War, which led to huge environmental damage and illnesses among the population and soldiers. In agriculture, including viticulture, it has been used since 1941 as a growth-inhibiting herbicide against weeds and as a pesticide and is particularly effective against knotweed, camomile and thistles. It is not considered to be completely environmentally friendly, but it is used in dosed form in integrated plant protection. See also under Plant protection and Vine enemies.
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