Tri-allate

Under very dry conditions, tri-allate can persist in soil for several months, and can damage field oats and sorghum. Degradation is dependent on soil microörganisms and moisture levels. Tri-allate is nontoxic to birds and bees, though it is very toxic to aquatic life. It doesn't bioaccumulate in plants, and has low mobility in soil. The aquatic toxicity is most potent against invertebrates and algae. The EPA says "the overall ecological risk associated with the use of triallate is low".

The average soil half life is 82 days in "typical" conditions; it is also measured at 46 days, under "field" conditions. Similar half-life is seen in water sediment and in acidic (pH 9) solution.

Triallate is synthesised from diisopropylamine, phosgene and 2,3,4-trichloro-phenyl-1-thiol.{{cite web |title=Source Assessment : Pesticide Manufacturing Air Emissions, Overview and Prioritization |url=https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=9101Y8ME.txt |website=nepis.epa.gov |date=1978}} Its surface tension is 0.049 N/m, as a 90% solution at 20 °C. Monsanto manufactured it in the 1960s by the reaction of diisopropylthiocarbamate salt with 1,1,1,3-tetrachloro-propene. It is soluble in acetone, ether, ethyl alcohol, heptane, benzene, ethyl acetate and most organic solvents.

Diallate is almost identical, but missing one of triallate's 3 chlorine atoms. Unlike triallate, it has cis- and trans- isomers.

Exposure to large amounts of tri-allate may harm the liver, spleen and kidneys. The EPA considers tri-allate to be a possible carcinogen, the result being "borderline" statistically significant in a trial on mice, though their rough estimate is that the chance of cancer from dietary triallate is one in 14 million. This trial only showed an increased incidence of tumors in one measured category, in a sample size of 15. Diallate, a very similar herbicide, was carcinogenic, possibly prompting the concern for triallate.

In tests on rabbits, no fetotoxic or teratogenic effects were observed, although a small decrease of birth weight was strongly evidenced.

Tri-allate is limited to the US states of California, Colorado, Idaho, Kansas, Minnesota, Montana, Nebraska, Nevada, North Dakota, Oregon, South Dakota, Utah, Washington and Wyoming, as of 2023. In Australia, all states allow it to control wild oats and most allow its broader use in combination with trifluralin. It is used in the United Kingdom, Morrocco and the EU states of Belgium, France, Ireland and the Netherlands.

It is incorporated to soil pre-sowing or (IBS) incorporated by sowing,{{cite web |title=4Farmers Tri-Allate 500 EC Leaflet |url=https://4farmers.com.au/wp-content/uploads/2018/06/63450-Tri-Allate-500-Leaflet-297x210-1.pdf |publisher=4Farmers Australia}} and is applied immediately before or up to 3 weeks before sowing. It is recommended to incorporate it 2–4 cm deep, and within 6 hours if the soil is moist, or 24 hours if dry, to minimise volatilisation. Proper incorporation is essential for efficacy,{{cite web |title=4Farmers Tri-Allate 500 EC Infosheet |url=https://4farmers.com.au/wp-content/uploads/2018/06/4F-Tri-Allate-500-EC.pdf |publisher=4Farmers Australia}} and two-pass incorporation is needed for maximum efficacy. Efficacy can also be reduced if the top 2 cm of soil is very dry.

Tri-allate is applied at 0.8-1.0 kg/Ha (0.71-0.89 lbs/ac) in Australia, with a spraywater volume of 30 to 100 L/Ha (3.2-10.7 US gal/ac). Triallate is sold as an emulsifiable concentrate of 500 g/L active ingredient.

Tri-allate is compatible with spray mixes containing chlorsulfuron, diclofop-methyl, trifluralin, glyphosate and oryzalin.

Tri-allate is applied to wheat, triticale, chickpeas, barley, peas, linseed, lupins, canola, faba beans and safflower. It was used on canary grass, but this registration was not renewed by the manufacturers, circa 2000.

Tri-allate is used to control wild oats, annual ryegrass, wireweed, phalaris spp, fumitory, cereal oats, sand fescue, silvergrass, wintergrass, paradoxa grass (canary grass), corn gromwell (sheepweed) and rough poppy. It supresses brome grass, barleygrass, cornered jack (doublegee), caltrop (yellowvine & bullhead), yellow burr weed, deadnettle and speedwell.

Triallate has been sold as Avadex, Buckle, Far-Go, Showdown,{{cite web |title=EXTOXNET PIP - TRIALLATE |url=http://extoxnet.orst.edu/pips/trialla.htm |website=extoxnet.orst.edu}} Check Mate,{{cite web |title=Apparent Check Mate 20L Active: 500g/L Triallate Comparable to Nufarm Avadex Xtra |url=https://www.fmb.com.au/apparent-check-mate-20l-active-500g-l-triallate-comparable-to-nufarm-avadex-xtra.html |website=www.fmb.com.au |access-date=17 May 2025 |language=en}} Triallate Gold,{{cite web |title=Genfarm Triallate Gold 500 Selective Herbicide |url=https://www.genfarm.com.au/crop-protection/herbicides/genfarm-triallate-gold-500-selective-herbicide |website=Genfarm |language=en}} Triallate{{cite web |title=Tri-Allate 500 EC Herbicide |url=https://www.imtrade.com.au/product/tri-allate-500-ec-herbicide/ |website=Imtrade CropScience}} and Tri-Allate.{{cite web |title=TRI-ALLATE 500 EC {{!}} 4Farmers |url=https://4farmers.com.au/products/herbicides/triallate-500ec/ |website=4farmers.com.au |publisher=4Farmers Australia}}

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{{Herbicides}}

Category:Group 15 herbicides

Category:Thiocarbamates

Category:Diisopropylamino compounds

Category:Organochlorides