Triclopyr: Difference between revisions

{{short description|Chemical compound used as a herbicide}}

{{Chembox

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| verifiedrevid = 451684386

| ImageAlt = Skeletal formula of triclopyr

| ImageFile1 = Space filling picture of.Triclopyr of better quality.png

| ImageAlt1 = Space-filling model of the triclopyr molecule

| PIN = [(3,5,6-Trichloropyridin-2-yl)oxy]acetic acid

| OtherNames = 3,5,6-TPA; Trident (Agriphar)

|Section1={{Chembox Identifiers

| CASNo_Ref = {{cascite|correct|??}}

| PubChem = 41428

| ChemSpiderID_Ref = {{chemspidercite|changed|chemspider}}

| ChemSpiderID = 37801

| SMILES2 = C1=C(C(=NC(=C1Cl)Cl)OCC(=O)O)Cl

| InChIKey = REEQLXCGVXDJSQ-UHFFFAOYAE

| StdInChI_Ref = {{stdinchicite|changed|chemspider}}

| StdInChI = 1S/C7H4Cl3NO3/c8-3-1-4(9)7(11-6(3)10)14-2-5(12)13/h1H,2H2,(H,12,13)

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| StdInChIKey = REEQLXCGVXDJSQ-UHFFFAOYSA-N

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| ChEBI = 9682

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|Section2={{Chembox Properties

| C=7 | H=4 | Cl=3 | N=1 | O=3

| Density =

| MeltingPtC = 148 to 150

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| SolubleOther = 989 g/kg

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'''Triclopyr''' ('''3,5,6-trichloro-2-pyridinyloxyacetic acid''') is an [[organic compound]] in the [[pyridine]] group that is used as a systemic foliar [[herbicide]]<ref name=Ullmann>{{cite journal|last1=Appleby|first1=Arnold P.|last2=Müller|first2=Franz|last3=Carpy|first3=Serge|title=Weed Control|journal=Ullmann's Encyclopedia of Industrial Chemistry|date=2001|doi=10.1002/14356007.a28_165|isbn=3-527-30673-0}}</ref> and [[fungicide]].<ref name="SoyResearch">{{cite book|last1=Shanmugasundaram|first1=S.|last2=Yeh|first2=C.C.|last3=Hartman|first3=G.L.|last4=Talekar|first4=N.S.|title=Vegetable Soybean Research Needs for Production and Quality Improvement|date=1991|publisher=Asian Vegetable Research and Development Center|location=Taipei|isbn=9789290580478|pages=86–87|url=http://pdf.usaid.gov/pdf_docs/PNABK804.pdf|accessdate=6 February 2016}}</ref>

== Uses ==

Triclopyr is used to control broadleaf weeds while leaving grasses and [[Cleaning (forestry)|conifers unaffected]]<ref name=Ullmann /> or to control [[Rust (fungus)|rust]] diseases on crops.<ref name="SoyResearch" />

Triclopyr is effective on woody plants and is used for brush control in the right-of-way and defoliation of wooded areas. In the USA, it is sold under the trade names Garlon, Remedy, and many others, and in the UK as SBK 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]].

== Environmental effects ==

Triclopyr breaks down in soil with a half-life between 30 and 90 days. It degrades rapidly in water, and remains active in decaying vegetation for about 3 months.<ref name="Environmental Fate Of Triclopyr">[http://www.cdpr.ca.gov/docs/emon/pubs/fatememo/triclopyr.pdf ''Environmental Fate Of Triclopyr''], Carissa Ganapathy, Environmental Monitoring & Pest Management Branch Department of Pesticide Regulation Sacramento, CA (dead link 23 October 2023)</ref>

The compound is slightly toxic to ducks ([[Median lethal dose|LD₅₀]] = 1698&nbsp;mg/kg) and quail (LD₅₀ = 3000&nbsp;mg/kg).<ref>[http://extoxnet.orst.edu/pips/triclopy.htm EXTOXNET (Extension Toxicology Network), Oregon State University]</ref> It has been found nontoxic to bees and very slightly toxic to fish (rainbow trout LC₅₀ (96 hr) = 117 ppm).<ref name="Environmental Fate Of Triclopyr"/>

Garlon's fact sheet for their triclopyr ester product indicates that triclopyr is highly toxic to fish, aquatic plants, and aquatic invertebrates, and should never be used in waterways, wetlands, or other sensitive habitats.<ref>{{cite web | url = https://pestweb.ca/assets/files/productdocuments/doc_C948965A0C05E3C7FF9F75BAB6BA06ABDFB17CD8.pdf | title = Garlon XRT Herbicide }}</ref> This is only for the triclopyr ester product, not for the triclopyr amine product.

== References ==

{{reflist}}

== External links ==

* [http://npic.orst.edu/factsheets/archive/triclotech.pdf archived Triclopyr Technical Fact Sheet – National Pesticide Information Center]

* [http://npic.orst.edu/factsheets/triclogen.pdf Triclopyr General Fact Sheet – National Pesticide Information Center]

* [http://extoxnet.orst.edu/pips/triclopy.htm Triclopyr Pesticide Information Profile – Extension Toxicology Network]

* {{PPDB|659}}

[[Category:Auxinic herbicides]]

[[Category:Chloropyridines]]

[[Category:Ethers]]

[[Category:Fungicides]]

[[Category:Pyridines]]