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Misuse of glyphosate can create market risk

Misuse of glyphosate can create market risk

Improper application leaves residue in the plant


By Jonathan Martin
Staff Writer

Misusing crop protection products can jeopardize growers’ investments, create market risk and jeopardize market access for all ag commodities.

If growers apply pre-harvest glyphosate when seed moisture content is above 30 per cent, the plant may absorb some of the product, leaving residues behind.

The Canola Council of Canada, Cereals Canada and Pulse Canada joined forces to spread the message through their Keep it Clean! initiative.

Greg Bartley manages crop protection and crop quality for Pulse Canada. He spoke to about the effect glyphosate contamination could have on Canadian ag’s international access.

“To avoid (developing) unacceptable levels (of the herbicide in your crop), glyphosate should be used for pre-harvest perennial weed-control, but not as a desiccant,” he told

Producers use desiccants to dry down crops and speed up maturity. Glyphosate, on the other hand, is a systemic herbicide, which crops absorb through their roots or foliage and move throughout the plant.

It could take weeks for a crop to die back after applying glyphosate, whereas a crop which received an application of true desiccant would only take days.

“When we see farmers apply glyphosate too early, we see residue beyond the maximum allowable limit,” Bartley said. “The limit varies depending on where you’re sending your product. Some countries follow the Codex (Alimentarius) Standard, but some have adopted their own national list, where the limit might be lower.”

Different grains and pulses have different limits, too.

If Canadian products break the rules too often, it might hurt the country’s reputation as a high-quality exporter, Bentley said.

“This is something that affects all producers, which is why we have to work together,” he said.

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Comments (4)

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in 1993 the allowable safety limits of glyphosate on oats was set at 0.1 ppb in1998 it was raised to 20 ppb in2008 it was raised to 30 ppb no new studies were done the EPA just raised the allowable limits ln 1993 the cheerios you buy in the store today would have poisoned you now the EPA says its OK grow and go organic
jim seaton |Jul 11 2019 2:56PM
Very interesting that this news is finally coming to light. This has been a concern of my fathers and mine for several years now after speaking with a hutterite farmer in Manitoba who stopped applying glyphosate to his crops after he found glyphosate residue in his dairy cows milk.
David Ross |Jul 11 2019 1:01PM
Never mind discussing at what stage to use glysophate pre harvest. It should be disallowed totally. You get just as good weed control post as pre. Can you imagine the dust residue that is on the seed after the harvest. The writing is on the wall. Act on the message, or you can wait for a disaster; and then blame someone else.
Mel Podaima |Jul 11 2019 10:32AM
This practice is endangering the continued use of glyphosate for all of us. The pre harvest use should be banned completely. I don’t like headlines that there is glyphosate in my cereal because of some other farmers careless use of it.
Rod Ricker |Jul 11 2019 7:24AM