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Staying a step ahead of weed resistance in the corn field

February 16, 2023  Sponsored by Bayer Crop Science

Weed resistance should be a consideration for every crop, and with the increasing presence of glyphosate-resistant weeds, it has become a growing area of concern for farmers. Planning a strong and diverse weed management strategy is the best way to support each crop and protect your investment from seeding to harvest.

Adapting your crop protection strategy to the fluctuations of each season is key to managing resistance and protecting your corn field. Adam Pfeffer, Market Development Manager for Row Crops at Bayer, shares two strategies to ensure that farmers are equipped with the best tools for managing weeds to maximize their corn yields in 2023.

Diversify your crop protection

With a robust crop protection market, there are a wide range of options for farmers to choose from. An easy way to manage resistance is the incorporation of a two-pass weed control program. Pfeffer recommends that, “when you start with your best soil-applied herbicide, you can follow it up with a post-emergent herbicide to manage any weeds that escape.” Choosing one Group 27 option with multiple tank-mix partners – such as Corvus™ or Laudis® herbicides – provides further protection with the integration of additional effective modes of action.

When weeds are a threat early in the growing season, Pfeffer recommends Corvus herbicide as a pre-emergence option for use on broadleaf and grass weeds. Corvus delivers three levels of control – rapid burndown for emerged weeds, residual control to prevent newly emerging weeds and reactivation with rain for prolonged weed control. Corvus can be used as a standalone product or can be used in a tank-mix with herbicides such as the Roundup® herbicide brands, Roundup Xtend® 2 herbicide with VaporGrip® Technology, XtendiMax® 2 herbicide with VaporGrip® Technology and atrazine for particularly tough to control weeds.

Alternatively, if farmers are looking to defend against troublesome broadleaf weeds, Pfeffer likes to have Laudis, a post emergence herbicide, in his back pocket as an effective, two-pass solution. This herbicide performs exceptionally well as a tank-mix partner with Roundup brands, Pardner® herbicide and atrazine. For improved control of Canada fleabane, Laudis can be used in a tank mix with Roundup Xtend 2 with VaporGrip® Technology or XtendiMax 2 with VaporGrip® Technology.

Solving problems as they emerge

With active scouting practices from pre-emerge to harvest, farmers can monitor for weed outbreaks and resistance early, and minimize the damage to yield potential. With an increase of Canada fleabane and waterhemp in Eastern Canada year over year, having a reliable solution at the first sign of trouble can make the difference in turning a mediocre yield into a great yield. For farmers that choose a two-pass program, fields can be treated at pre-emerge application, followed by an in-crop application that is fine-tuned to the needs of the field. Laudis, for example, in combination with Pardner or atrazine as the second part of a two-pass program, serves as an excellent cleanup treatment for waterhemp.

Implementing a comprehensive weed management strategy can help mitigate future resistance while protecting the yield of your corn crop. For more information about how you can manage resistant weeds, speak with your local Bayer representative or visit

ALWAYS READ AND FOLLOW PESTICIDE LABEL DIRECTIONS. Bayer, Bayer Cross, Corvus™, Laudis®, Pardner®, Roundup®, Roundup WeatherMAX®, Roundup Xtend®, Transorb®, VaporGrip® and XtendiMax® are trademarks of Bayer Group. Used under license. All other trademarks are the property of their respective owners. Bayer CropScience Inc. is a member of CropLife Canada. ©2023 Bayer Group. All rights reserved.


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