Beyond rotating modes-of-action: preventing herbicide resistance with cultural controls


Herbicide resistance will sneak up on you if you don’t change up your management practices from time to time.

Steve Shirtliffe works to help farmers develop strategies to keep resistance issues at bay. He is a professor at the University of Saskatchewan, and I caught up to him at the recent CropConnect conference at Winnipeg, Manitoba.

“We look at elements of weed control, in most cases not herbicidal,” says Shirtliffe, “but using different cultural or mechanical ways to control weeds that, perhaps in combination with herbicides, would work better.” Generally speaking, the idea is not to replace herbicides, but to make them more effective, and to slow down the potential onset of resistance.

Shirtliffe stresses the importance of empirical evidence. “Our approach has been to not just recommend a practice because we think it is a good idea, but to go out and test it.”

Research in this area really requires “thinking outside the box.” In this case the box is the toolbox, so to speak, that contains the different options that farmers have available to them. Mother Nature is always changing — there are different environmental conditions, incursions of different weed species, and, in some cases, genetic mutations, all of which erode the efficiency of any given farming practice. This is why new solutions have to be continually sought after and incorporated into production methods.

One good example of an alternate strategy is simply making sure the ground is covered. Shirtliffe says, “When you’re growing crops, what you’re trying to do is build a solar panel, and the quicker that you can have that crop form a canopy that blocks off the light and therefore they can use that energy to build yield in the crop, the quicker you can do that and the more it can shade it out it actually has a weed control benefit.”

Watch the entire interview with Steve Shirtliffe, professor, University of Saskatchewan, below. 

Wake up with RealAgriculture

Subscribe to our daily newsletters to keep you up-to-date with our latest coverage every morning.

Wake up with RealAgriculture

Please register to read and comment.


Register for a RealAgriculture account to manage your Shortcut menu instead of the default.