Wheat School: Assessing spray pass effectiveness in the face of growing herbicide resistance


Whether you are a farmer, rancher, agronomist, researcher, or industry professional — you’ve likely encountered herbicide resistance.

We know herbicide resistance is out there, and unfortunately, there’s no silver bullet to managing it. However, as Rob Klewchuk of Syngenta Canada explains in this Wheat School episode, there are some management things that can be done. There are quite a few options and they can’t all be done on each field or operation, so it’s key to find which ones work for the situation being encountered.

“Delaying seeding allows your weeds to emerge. And then you can kill them,” Klewchuk explains. A complex crop rotation means using different products in rotation, too, and changes competition. Rotating effective herbicide groups is key, too.

One of the management options that can be daunting, but effective, say Klewchuk, is not just looking at what herbicides are applied — but how they are applied.

“You can talk about sprayer speed. Slow your sprayer down,” he says. “Could you increase your water volume to increase your chances of hitting those weeds? Also, lower your booms, so you’re hitting that target.”

As well, it’s important to pay attention to weed patches in fields and determining why they weeds didn’t die. It could be an application or mechanical error, but it could be a herbicide resistance issue.

“Mark those patches that didn’t die. Now let’s try to figure this patch out before it becomes a big problem on this piece of land,” he says.

Learn more in the Wheat School episode, below:

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Wheat School (view all)Season 14 (2023) Episode 5

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