If farmers keep misusing glyphosate, they may lose it

The warnings from the ‘Keep it Clean’ campaign are taking on a more urgent tone

Keep it Clean wants farmers to hear the message that glyphosate and other crop protection products need to be applied only according to the label.

If Canadian farmers want to keep using glyphosate they must stop misusing glyphosate.

That blunt message was delivered earlier this summer during a ‘Keep it Clean’ webinar to agronomists and retailers, who were urged to pass it on to their farmer-clients.

“We all know the value of glyphosate, but to be very blunt about it, if we don’t use this product correctly the marketplace is going to begin to take it away from us,” Cereals Canada president Cam Dahl said. “It’s not going to be government regulations that limit the use of glyphosate, it is going to be our customers’ demand.”

He added farmers need to hear the message that keeping “very valuable” tools like glyphosate and other crop protection products will depend on always using it according to the label.

Farmers are also being urged to minimize crop diseases to preserve markets.

Why it matters: Canadian grain and oilseed production relies heavily on exports, which requires market access. In an increasingly protectionist world some countries are looking for excuses to block imports.

Dahl, and the other presenters, Brian Innes, vice-president of communications at the Canola Council of Canada and Mac Ross, Pulse Canada’s manager of market access and trade policy, stressed glyphosate is not a desiccant. It’s registered for pre-harvest weed control. It shouldn’t be applied unless canola, cereals and pulse seeds are less than 30 per cent moisture.

Crops must have reached physiological maturity, even in the least mature part of the field.

“If it’s applied to a green crop we are seeing that (glyphosate) residue comes from the inside of the seed,” Dahl said.

x photo: Canola Council of Canada

Thirty per cent seed moisture in canola occurs at 50 to 60 per cent colour change, which is when a farmer would swath, Innes said.

Glyphosate is coming under scrutiny. Several plaintiffs claiming their cancer was caused by glyphosate have successfully sued Bayer in the United States for billions of dollars. Most world regulations, including Health Canada, say glyphosate is not a carcinogen and is safe when label instructions are followed.

“It’s no surprise to anyone… the amount of scrutiny that glyphosate has come under globally and in some of our key export markets,” Ross said. “It really has underscored the importance of following labelled rates and labelled application timing.”

Italy, once Canada’s biggest durum customer, has cut imports due to consumer concerns fanned by domestic durum farmers about glyphosate residues, even though they are within allowable limits.

Glyphosate is registered for many crops in Canada, but some oat buyers don’t allow its use, Dahl said.

Malting barley buyers also don’t allow glyphosate use because it affects germination, which is critical to the malting process.

Some edible bean buyers don’t allow glyphosate use either.

The same applies to some other pesticides. Farmers should check the Keep it Clean website and consult with buyers before using pesticides, Ross said.

Some farmers doubt what a few others do can affect the whole crop, but it does, especially now because technology can detect minute pesticide residues, Dahl said.

“The threat is very real and we’re seeing it in the marketplace today,” he said.

“If I have a take-home message about the ‘Keep it Clean’ program… what happens on the farm really does matter in the international marketplace and it has an impact on the value of Canadian crops.”

Press a thumbnail into the kernel with moderate pressure. If the indent bounces back, the crop is not dry enough to receive glyphosate application. photo: Keep it Clean

Many countries have a maximum residue limit (MRL) for pesticides, Innes said. An MRL is much lower than what’s considered safe and is meant to show a pesticide was applied according to the label, he said.

In some cases where there’s no MRL there is no tolerance for any residue, Innes said.

That’s the case for malathion on canola. That’s why canola must not be stored in bins where malathion was used to control grain insects, he added.

Plant diseases in crops can also close borders. China blocked canola imports from Canada in 2009 over concerns Canada’s strain of the fungal disease blackleg, which reduces canola yields, could be transferred to China, Innes said.

Farmers should be scouting for infections before swathing to see how effective their control measures have been, he said.

Farmers should also be growing blackleg-resistant varieties.

Controlling the disease helps farmers, but also shows customers Canada is trying to minimize the risk to them, Innes said.

Canadian cereal buyers also don’t want the mycotoxin deoxynivalenol (DON), caused by the fungus disease fusarium head blight, in their grain because it can make people sick.

“This is something our customers pay attention to,” Dahl said.

Head blight doesn’t just hurt farmers by decreasing yields and crop value, but it can be a market barrier, he said.

Farmers should scout for the disease and apply a fungicide if warranted, Dahl said. They should also grow head blight-tolerant varieties, rotate crops and plant clean, treated seed.

Storing wheat cool and dry is also important to avoid another mycotoxin, ochratoxin A, Dahl said.

By publicly focusing on pesticide and disease issues, some farmers wonder if Canada is hurting itself. But Ross said it could give Canada an advantage by demonstrating Canada takes customer concerns seriously, Ross said.

Canada’s customers say Canada has a reputation for consistently delivering safe, high-quality crops, Dahl said.

“What happens on the farm matters,” he told the webinar. “The advice you give to farmers matters. We do need to protect our markets.”

Pre-harvest applications of glyphosate on cereals

Canadian cereal growers can protect their investment and help to maintain market access for everyone by carefully planning and managing pre-harvest glyphosate applications. The following special considerations should be taken when applying glyphosate pre-harvest:

Wheat: Only use pre-harvest if greenest part of the crop is less than 30 per cent moisture.
Oats: Only use pre-harvest if greenest part of the crop is less than 30 per cent moisture and talk to your buyer, oats may not be accepted by grain buyers if treated pre-harvest.
Malt barley: Will not be accepted by grain buyers if treated pre-harvest.

Canola and glyphosate

Apply at 50-60 per cent seed colour change to avoid unacceptable residues.

  • Only use for pre-harvest weed control once seed moisture is less than 30 per cent
  • By applying at 50-60 per cent seed colour change in the least mature areas of the field, growers can be confident seed moisture will be less than 30 per cent

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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