Triclopyr

Triclopyr (3,5,6-Trichloro-2-pyridinyloxyacetic acid) is an organic compound in the pyridine group that is used as a systemic, foliar herbicide and fungicide.

Uses

Triclopyr is used to control broadleaf weeds while leaving grasses and conifers unaffected or to control rust diseases on crops.

Triclopyr is effective on woody plants and is used for brush control in rights of way and defoliation of wooded areas. In the USA it is sold under the trade names Garlon and Release, and in the UK as SBK, Shrub and Brushwood Killer.

It is also used for broadleaf weeds, particularly Creeping Charlie (Glechoma hederacea). It is sold under the trade names Turflon, Weed-B-Gon (purple label), and Brush-B-Gon ("Poison Ivy Killer") for these purposes. It is a major ingredient in Confront, which was withdrawn from most uses due to concerns about compost contamination from the other major ingredient, clopyralid.

Triclopyr is formulated both as an ester and as an amine salt. The usual tradeoffs regarding effectiveness, drift, and toxicity to humans apply to these two formulations. It is chemically very similar to the herbicide which it generally replaces, 2,4,5-T, which was phased out in the U.S. in the 1970s amid toxicity concerns.