Combat Herbicide-Resistant Soybean Weeds With Integrated Management

If a weed-free field seems like your ultimate harvesting dream, then herbicide-resistant weeds have to be your worst nightmare.
For years, new cases of resistance have emerged across the Midwest, with problem weeds like kochia, common waterhemp and common ragweed developing resistance to several different herbicides. These resilient species are a direct threat to yield, profitability and long-term weed control.

As resistance spreads, traditional herbicide programs alone are no longer enough. That’s why a proactive, integrated management strategy combining crop rotation, herbicide diversity and herbicide-tolerant soybean traits is now essential.
Let’s explore how these strategies work together to protect your soybean crop and preserve herbicide effectiveness for seasons to come.

Integrated weed management to control soybean weeds

Integrated weed management is the opposite of a spray-and-pray strategy. It considers all aspects of soybean weed control, including mechanical, cultural and chemical.
Rotating crops can be a simple way to disrupt the life cycles of common soybean weeds, allowing for the use of different control strategies. Different crops create different canopy structures, planting times and harvest windows, which prevents weeds in soybeans from adapting to a predictable environment.¹

Tillage can be a useful tool if you have a history of herbicide-resistant weeds in your fields and have exhausted your chemical options. While no one wants to overuse tillage, incorporating occasional mechanical control, combined with strategic burndown, can help limit reliance on post-emergence herbicides.
When it comes to getting ahead of weed pressure, knowing what you’re up against makes all the difference. Scouting your fields regularly (and not just from the seat of your truck) can help you manage escapes that might replenish the seed bank.

Managing herbicide resistance in soybeans

One of the reasons herbicide resistance continues to develop so quickly in weeds is the exclusive and repeated use of the same herbicide mode of action (MOA). Simply applying more of the same herbicide won’t make a difference if the weeds in your field are developing resistance to that product’s MOA.
When herbicide-resistant weeds survive a chemical application, they pass that trait on, gradually shifting the population until entire fields stop responding to that herbicide. To delay that shift, your herbicide strategy must reduce the chance of any one weed surviving.

Applying a soybean pre-emergence herbicide with multiple modes of action can impact different biological pathways within the plant. Using a pre-emergence soybean herbicide early in the season lays the groundwork for effective control before weeds ever emerge. If none of those weeds can produce seeds and pass on those resistant traits, your chemistry toolbox can continue to work.
A single active ingredient may suppress weeds temporarily, but without multiple MOAs, your risk of weed species adapting and overcoming the effects of the herbicide is increased.
Avoid using the same MOA repeatedly in the same season or year-over-year. Even if the chemistry is still working, repeated exposure increases the odds of selecting for resistance. Instead, rotate between modes of action and combine pre- and post-emergence applications with different MOAs that are effective on problem weeds when appropriate.²

Emerging technologies for herbicide-resistant soybean weeds

Fortunately for Midwest soybean growers, new herbicide-tolerant soybean traits are providing more flexibility and stronger tools for managing resistant weeds.
These technologies enable you to rotate and layer herbicide modes of action more effectively, which is crucial in slowing the development of resistance. Instead of being limited to a narrow set of post-emergence options, these traits expand your chemical playbook.

For example, Xitavo® and Enlist E3® soybeans offer tolerance to 2,4-D choline (Enlist), glyphosate and glufosinate. This provides growers with multiple modes of action to utilize within a single season.
This enables farmers to manage resistance more strategically by rotating herbicide tools both within and across seasons. As weed pressure intensifies, new soybean traits are becoming one of the most important tools for preserving the long-term effectiveness of herbicides.

Experts are available to help you make your decisions. Reach out to your seed retailer, a nearby extension office agent, or a seed company professional like your regional BASF representative.

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Endnotes

1. Proctor, Chris, and Rodrigo Werle. “Keys to Managing Herbicide Resistance in Soybeans.” CropWatch, 6 Apr. 2017, University of Nebraska–Lincoln, https://cropwatch.unl.edu/2017/keys-managing-herbicide-resistance-soybeans/.
2. Barnes, Ethann, John Lindquist, Stevan Knezevic, and Amit Jhala. “Herbicide Options for Managing Glyphosate‑Resistant Common Ragweed in LibertyLink Soybean.” CropWatch, 1 Mar. 2018, University of Nebraska–Lincoln, https://cropwatch.unl.edu/2018/herbicide-options-managing-glyphosate-resistant-common-ragweed-libertylink-soybean/.
3. Barnes, Lindquist, and Jhala. “Herbicide Options for Managing Glyphosate‑Resistant Common Ragweed in LibertyLink Soybean.”