Search For New Herbicides Continues

For Len Juras, hunting for new herbicides is a bit like living in one of those country-western “hurtin” songs – minus the twang of course.

“The biggest lesson I’ve had to learn is letting go,” the senior research scientist for Dow AgroSciences said here last week.

“Over the years I’ve had my heart broken many a time – I feel like a country-western singer because you have something that works great for Canada, but because it’s not fitting anywhere else on the globe, it just dies on the vine.”

The cold, heartless fact about the herbicide business is that a new compound, no matter how useful it might be to a specific region, must be able to earn at least $100 million per year before the company will even consider developing it.


After all, it takes about 10 years and millions of dollars in testing to prove a product’s safety and efficacy before a new discovery makes it to a farmer’s field. Only then can its developer start collecting a return on investment.

Researchers work early on with company marketing people to assess a new product’s potential. It boils down to weighing the potential benefits against the risks, Juras said.

“A rule of thumb in the industry is that only one out of every 100,000 compounds makes it,” Juras said. “I’d say it’s even lower than that.”

But while plant biotechnology is grabbing the headlines, Dow officials say they are continuing to hunt for potentially useful herbicide combinations, screening 100,000 compounds annually at the company’s headquarters in Indianapolis, Juras said.

“I think it’s still a very important area for agriculture,” Dow AgroSciences Canada president and CEO Jim Wispinski told reporters during a July 26 tour of Dow AgroSciences’ research plots. “Mother Nature is very resilient and continues to adapt so we need to continually invest in agricultural research to allow us to stay one step ahead in providing solutions to the growers.”

When glyphosate-tolerant

crops hit the market some thought other herbicides would become redundant. But soon it became clear there’s no one solution to controlling weeds, Juras said.


While Dow AgroSciences is searching for new herbicides, it’s also trying to improve the ones it already has, said Kelly Bennett, Dow AgroSciences portfolio leader for cereal herbicides. Sometimes that involves combining two herbicides.

“We put them together in a formulation and sometimes some magic happens,” Bennett said.

“In the right combination you can build very powerful solutions.”

Bennett says Dow AgroSciences’ Stellar herbicide is a good example. It’s a combination of florasulam and fluroxypyr. Florasulam provided outstanding control of cleavers until they developed resistance to Group 2 herbicide. Fluroxypyr, a Group 4 weed killer, also works on cleavers. Stellar, which also contains MCPA, is a “powerful” tool for managing Group 2-resistant cleavers, he said.

Meanwhile, Dow Agro- Sciences researchers are finding new ways to tweak some of the company’s existing herbicides to provide new weed control options, he said.

Dow AgroSciences recently introduced two new herbicides to Western Canada – Tandem and OcT Tain. Tandem is a grass and broadleaf weed killer. OcTTain, designed for the brown and dark-brown soil zones of the southern Prairies, controls broadleaf weed.


Tandem is a combination of two active ingredients – pyroxsulam (Group 2), which is also in Dow AgroSciences’ Simplicity herbicide, and fluroxypyr (Group 4).

In most cases Tandem should be tank mixed with either 2,4-D or MCPA for complete annual weed control.

OcTTain is a combination product similar to Attain (fluroxypyr and 2,4-D Ester), but is designed to deliver weed control optimized for the brown and dark-brown soil zones.

OcT Ta i n , compared to the low rate of Attain, will deliver more powerful control of a number of key weeds. Most important are wild buckwheat (one-to six-leaf stage) and kochia up to the 10- to 15-cm range, including Group 2-resistant biotypes.

OcTTain will also add control of volunteer flax and stork’s bill as well as suppression of Canada thistle, sow thistle and dandelion.

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Thebiggestlesson I’vehadtolearn islettinggo.”


About the author


Allan Dawson

Allan Dawson is a reporter with the Manitoba Co-operator based near Miami, Man. Covering agriculture since 1980, Dawson has spent most of his career with the Co-operator except for several years with Farmers’ Independent Weekly and before that a Morden-Winkler area radio station.



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