Even if you don’t think you have herbicide resistant weeds in your fields, the best management practice might be to treat your fields as if you do.
That’s the advice of Linda Hall, associate professor in the Faculty of Agriculture Life and Environmental Science at University of Alberta, in this episode of the Resistance Management School.
There is a tendency to want to find a convenient scapegoat when dealing with herbicide resistance weeds, but the truth is, nature is a complex system that adapts to whatever activity is repeated. The real culprit is natural selection. “Herbicides are a great tool, but we have been using the same tools over and over again so natural selection is what is creating our resistance problems,” she says.
Hall explains that each weed species exhibiting resistance must be dealt with on its own merits — there is no one-size-fits-all solution. Crop and herbicide rotations are still good tools. Having a good understanding of herbicide makeup is key, she notes, so that the same chemical family is not used repeatedly
There are still several different herbicide options that are available for wild oat, for example. For kochia, on the other hand, we have to dig a little deeper. Most of our “easy” chemical options have been used up so other management strategies and more complex herbicide mixing is a must. And you simply can’t let suspected resistant plants go to seed; they’ll spread far too quickly.
“The best advice for growers that don’t think they have resistance is to act like they do,” she says.