Farmers urged to follow markets, not labels, on chemical residue

Getting it dried down - Producers might need to begin thinking earlier in the year about harvesting strategies for their pulse crops. With tricky MRL limits for the dessicant diquat and more strictly enforced use of the herbicide glyphosate, swathing crop such as lentils may once again be they way farmers dry things down.   |  Michael Raine photo

Following the label isn’t enough.

In today’s fraught world trading environment, meeting label requirements with products under scrutiny in foreign markets could lead to disaster.

“Go talk to the buyer,” urged Greg Bartley, the manager of crop quality for Pulse Canada, in an interview.

“You need to pay attention to the MRLs (maximum residue limits) in our export (markets,) not the MRLs that are established here in Canada.”

This is true for all of Canada’s crops, but pulse crops are at particular jeopardy for MRL risk because 85 percent of the crop is exported. Canada has some MRL levels that are far higher than those in foreign markets, creating a significant risk of a farmer growing to Canadian standards and then falling afoul when his crop is shipped across the border.

Pre-harvest glyphosate has drawn much attention in recent years, with more foreign markets and commercial buyers testing for residue levels.

But diquat is a particular risk in pulse production. It’s a long-used desiccant in widespread use, with a Canadian MRL and ones in most foreign markets that don’t pose a problem for farmers applying it correctly.

However, the U.S. MRL for diqquat is only a tiny fraction of the Canadian level — about 1/18th – at 0.05 parts per million (ppm) versus 0.9 ppm for Canada.

A farmer could get caught in testing if his treated crop was shipped by container or rail, without being mixed into a major blended shipment as happens with major commercial shipments.

“Any crop being exported to the (United States), especially in a small lot shipment … has the potential to exceed that MRL,” said Bartley.

That’s why it’s vital for the grower to talk to the buyer before applying products in question. If that buyer is eyeing U.S. sales, he may not want the grower to be using a product like diquat. The same goes for a number of other products. A chat with the buyer can help the farmer ensure he is not inadvertently getting himself into trouble.

So far, few problems have arisen from Canadian sales to the U.S., even though the gulf in standards has existed for years. However, Bartley cautioned, the world trading environment has become much more protectionist, more testing is being done commercially and at borders, and chemical residues can become a handy way to block trade if a country wants to do that.

“MRLs are really coming to the forefront,” said Bartley. Last year dry bean growers discovered pre-harvest glyphosate was a problem for some buyers, causing a lot of anxiety and worry for those using it.

“That’s how things can change,” he said.

Reglone, diquat, offers the best option for producers looking to get a high quality crop into the bin. | Syngenta photo

The MRL issue is vexing for growers who need some way to dry down a crop or control late season weeds. That makes products like glyphosate and diquat tricky to manage. How to appropriately use them is detailed both by suppliers and by the Keep It Clean program, which contains simple and helpful explainers and diagrams.

On the Keep It Clean website is a “Swath to spray interval calculator”, which can help farmers figure out the pre-harvest interval required for safe application of some products.

The word “swath” is something many farmers don’t like hearing or thinking about these days, with most farmers trying to do all the straight combining they can to avoid extra operations and crop losses in the swath.

But the word is appearing more frequently these days as farmers juggle their options to preserve harvest quality and also avoid MRL issues.

Whatever way farmers decide to deal with products like diquat and glyphosate will depend on each farm’s unique situation.

But understanding the differences between label requirements and export sensitivities is becoming crucial.

And managing the crop requires understanding who might end up receiving it.

“It is up to the grain buyer to determine if that’s a risk or not,” said Bartley.

“It’s that acceptable product” for the buyer that’s essential, said Bartley.

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