Hoping To Prevent Resistance
Denny Myers, president of Myers Inc. in Lexington, IL, believes that an ounce of prevention is worth a pound of cure. Thatâ€™s why he encourages his grower-customers to use resistance management practices now â€” BEFORE weed resistance/tolerance settles into the area.
Myers Inc., a CropLife 100 dealership, has six outlets in central Illinois, an area relatively unscathed by glyphosate-resistant/-tolerant weeds â€” so far.
â€œThereâ€™s been some glyphosate resistance south of us, but we havenâ€™t run into too much of it here yet,â€� says Myers. â€œBut we have seen some resistance to ALS (acetolactate synthase) herbicides.â€�
Preventive measures against glyphosate resistance/tolerance boil down to different modes of actions and different timings for Myers Inc. customers.
â€œWe donâ€™t like to see a straight glyphosate program,â€� he says. The grower can still use glyphosate but should plan to add a residual in front or tank mix it with another herbicide with a different mode of action.
â€œYou try to use residuals, especially in the corn market,â€� he says. â€œUse acetochlor or a broadleaf compound. One option would be a Lexar- or Lumax-type product (both from Syngenta Crop Protection), Radius (Bayer CropScience), or SureStart (Dow AgroSciences). But we want to put a product down in front of the glyphosate.
â€œThatâ€™s going to help us get the small-seeded broadleaf weeds,â€� he explains. â€œWe want it for help on the pigweed and lambsquarters. And then youâ€™ll have a different mode of action for foxtail and other grasses as well.
â€œBut for giant ragweed, I guess you want to have something with a little more broadleaf kick in it, so use a little atrazine,â€� Myers says.
On the soybean side, ALS products can be used on broadleaf weeds. â€œOr you can put the yellow compound (Dow AgroSciencesâ€™ Treflan) or another residual down in front of glyphosate,â€� he says.
Unlike retailers dealing with resistant weeds, at this point Myers Inc. is not recommending changes in crop rotations.
â€œWeâ€™ve always been telling our growers that we want to have different modes of action so that we donâ€™t have resistance here,â€� he says. â€œIâ€™m sure that some day we are going to, but at this stage of the game, we havenâ€™t seen it yet. I do have some growers that I have putting the straight glyphosate on. Weâ€™ve been discouraging them from doing that, but whether they listen to you or not is another thing.â€�