Triclopyr
Encyclopedia
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 names Garlon and Release for these purposes.
Also handy for broadleaf weeds, particularly Creeping Charlie
(Glechoma hederacea
), upon which it is uncommonly effective. 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 It is a major ingredient in Confront, which was withdrawn from most uses due to concerns about compost contamination from the other major ingredient, clopyralid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.
The compound is slightly toxic to ducks (LD50 = 1698 mg/kg) and quail (LD50 = 3000 mg/kg). It has been found non-toxic to bees and very slightly toxic to fish (Rainbow trout LC50 (96 hrs.) = 117 ppm).
Herbicide
Herbicides, also commonly known as weedkillers, are pesticides used to kill unwanted plants. Selective herbicides kill specific targets while leaving the desired crop relatively unharmed. Some of these act by interfering with the growth of the weed and are often synthetic "imitations" of plant...
in the pyridine
Pyridine
Pyridine is a basic heterocyclic organic compound with the chemical formula C5H5N. It is structurally related to benzene, with one C-H group replaced by a nitrogen atom...
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 names Garlon and Release for these purposes.
Also handy for broadleaf weeds, particularly Creeping Charlie
Glechoma hederacea
Glechoma hederacea is an aromatic, perennial, evergreen creeper of the mint family Lamiaceae. It is commonly known as Ground-ivy, gill-over-the-ground or Creeping Charlie. It has numerous medicinal uses, and is commonly used as a tasty salad green in many countries...
(Glechoma hederacea
Glechoma hederacea
Glechoma hederacea is an aromatic, perennial, evergreen creeper of the mint family Lamiaceae. It is commonly known as Ground-ivy, gill-over-the-ground or Creeping Charlie. It has numerous medicinal uses, and is commonly used as a tasty salad green in many countries...
), upon which it is uncommonly effective. 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
Clopyralid
Clopyralid is a selective herbicide used for control of broadleaf weeds, especially thistles and clovers....
.
Triclopyr is formulated both as an ester
Ester
Esters are chemical compounds derived by reacting an oxoacid with a hydroxyl compound such as an alcohol or phenol. Esters are usually derived from an inorganic acid or organic acid in which at least one -OH group is replaced by an -O-alkyl group, and most commonly from carboxylic acids and...
and as an amine
Amine
Amines are organic compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are derivatives of ammonia, wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group. Important amines include amino acids, biogenic amines,...
salt. The usual tradeoffs regarding effectiveness, drift, and toxicity to humans apply to these two formulations.
Environmental Issues
Triclopyr breaks down in soil with a half-life of between 30 and 90 days. One of the byproducts of breakdown, trichloropyridinol, remains in the soil for up to a year. Triclopyr degrades rapidly in water. It remains active in decaying vegetation for about 3 months.The compound is slightly toxic to ducks (LD50 = 1698 mg/kg) and quail (LD50 = 3000 mg/kg). It has been found non-toxic to bees and very slightly toxic to fish (Rainbow trout LC50 (96 hrs.) = 117 ppm).