Triclopyr is a systemic, foliar herbicide in the pyridine group. It is used to control broadleaf weeds while leaving grasses and conifers unaffected.
Triclopyr is unusually effective on woody plants and is used for brush control in rights of way and defoliation of wooded areas. It is sold under the trade name Garlon for these purposes.
Also handy for broadleaf weeds, particularly Creeping Charlie, upon which it is uncommonly effective. It is sold under the trade names Turflon, and Weed-B-Gone (purple label) for these purposes. Also the second major ingredient in Confront, which also contains clopyralid, and was withdrawn from most uses due to concerns about compost contamination from the.clopyralid.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.