Multistate HERMON project tackling weed challenges across U.S. soybean belt.
Herbicide resistance isn’t a distant threat; it’s here, spreading and reshaping how growers manage soybean fields across the United States. As weed species like waterhemp, Palmer amaranth and ragweed adapt to withstand once-reliable herbicides, growers are left with fewer options and higher costs.
In some regions, yield losses from resistant weeds can top 50%, and many worry that new herbicide-tolerant traits — like Enlist and Xtend — could follow the same path as glyphosate-resistant systems without careful management.
Enter HERMON: the Herbicide Resistance Mitigation Outreach Network. This multistate initiative brings together weed scientists and diagnostic labs from across the soybean belt with a bold goal of standardizing diagnostics, sharing data and staying ahead of resistance before it takes root.
Led by Michigan State University’s Eric Patterson, HERMON goes beyond traditional research silos. It’s building a national diagnostic and response system, supporting both public extension and private innovation, while training a new generation of weed scientists who understand both growers’ needs and lab-based tools.
Seed World U.S. caught up with Patterson, an assistant professor and weed geneticist in the MSU Department of Plant, Soil and Microbial Sciences, to learn more about why HERMON is happening now, what makes it different and how seed companies and agronomists can play a key role in protecting soybean fields for the future.
SW: What makes the HERMON project different from previous herbicide resistance efforts, and why is now the right time to launch this kind of network?
Patterson: HERMON represents a concerted effort between universities spanning a large portion of the soybean-growing region. Previously, each university primarily worked within their states or in small regional groups and there wasn’t much exchange of germplasm or training.
Additionally, there are a vast number of opinions on how to characterize and classify a population of weeds as ‘resistant.’ In this project, we want to correct these issues by focusing on sharing results, exchanging unique germplasm and standardizing techniques to make a more cohesive university response to herbicide resistance.
This is especially timely in soybean, where new traits are being rolled out, and we don’t yet have widespread resistance to the herbicides used in these systems. Now is the time to be diligent in monitoring new resistance cases and tracking their spread to maintain the efficacy of these traits for as long as possible. We know from the RoundUp experience that overreliance on a few herbicides will inevitably result in widespread resistance, and we want to help avoid or at least slow that situation.
SW: How will standardizing resistance diagnostics across multiple universities directly impact seed companies and growers in the short term?
Patterson: There are several short and medium-term impacts for growers and industry. Immediately, we’ve set up a framework where growers can submit suspected cases of herbicide resistance in soybean to any of the participating PIs. We can then share those seeds throughout HERMON, test those plants in the greenhouse or lab, and get results back to the grower.
In the medium term, we’ll be developing rapid markers for resistance that could give results in just a few weeks instead of waiting until the next season. Some of these tools already exist but are limited to one or two labs. We want to make them available across all participating universities. With faster, more accurate information about resistance in the field, growers can make more educated decisions and better protect their yields year after year.
SW: MSU is serving as the northern diagnostic hub. What kind of weed threats are you seeing in this region that seed professionals should be paying closer attention to?
Patterson: We are interested in weeds that are well adapted to northern soybean production — namely waterhemp, marestail (horseweed) and ragweed. Further south, groups are more focused on Palmer amaranth and various grass weeds.
The big resistance threats across the soybean region are 2,4-D (Enlist) and Glufosinate (Liberty), which are critical for post-emergent weed control and have replaced some of what RoundUp used to handle. We’re also paying attention to weeds with stacked resistance traits—plants that can survive multiple independent applications or tank mixes. And PPO resistance, both pre- and post-emergence, is a big one, especially in non-GMO soybean. We’re currently investigating several Michigan ragweed populations for PPO resistance.
SW: What role do you see seed companies playing in the success of HERMON, particularly in implementing resistance management strategies?
Patterson: Resistance management is all about maintaining the shelf life of the new traits that the seed industry produces. We don’t expect new herbicides or novel technologies to hit the market in the immediate future, so it’s essential to preserve the tools we do have.
I know many companies already work hard to steward their traits internally. But as public-facing institutions, land-grant universities also have a responsibility to work directly with growers. I see HERMON as a bridge between industry and growers. We have the unique ability to communicate with both groups and understand their needs.
SW: You’ve mentioned training the next generation of weed scientists. What qualities or skills are you prioritizing in these future leaders?
Patterson: Now more than ever, I think graduate students need to be jacks-of-all-trades. Field scientists need to understand lab work, and lab scientists need to understand grower and industry priorities.
HERMON allows us to take a multi-faceted approach to a complex issue like herbicide resistance and train our students to think broadly while working toward specific research goals. We’re exposing them to experts across weed science — molecular, biochemical, physiological, and agronomic. Industry wants well-rounded scientists who solve meaningful problems quickly and effectively. They also need people who think outside the box to develop new molecules, new traits and entirely new weed-management strategies.
Other universities involved include Kansas State University, Mississippi State University, Penn State University, Purdue University, Texas A&M AgriLife Research, University of Arkansas, University of Illinois, University of Missouri and the University of Wisconsin.
