One More Pass: Late Season Scouting Can Improve Weed Control and ROI 

Identifying weed escapes now can sharpen your strategy, protect returns and set you up for next season’s success

As summer fades to fall, much of the focus for growers naturally shifts to crop output and harvest logistics. But in the rush to wrap up the season, it’s easy to overlook another key area that can impact both current and future yields: late-season weed management.

Scouting fields and orchards at this stage of the season is a critical step that can improve weed control efficacy, inform future herbicide decisions and ultimately protect return on investment (ROI).

It’s never too late to discover what’s going on in your fields. Learnings now can still lay the groundwork for better management decisions next season.

Know your weeds

Fluctuating weather patterns this spring in many parts of the country made it tough to hit critical weed management windows, especially for perennial and hard-to-control species.

As a result, problem weeds like Canada thistle, horseweed (marestail) and quackgrass have shown up across a range of cropping systems. Wilbur-Ellis agronomy experts urge growers not to wait until next spring to address these challenges.

“Now is a good time to scout fields and see what’s going on,” says Jake Ernst, Wilbur-Ellis branded technologies and biological solutions territory manager. “As you check fields, do you see escapes or notice some resistance? These are important things to know because when the combine goes through your field, it acts as a million-dollar weed seed spreader.”

For instance, kochia has been a problem weed in many corn and soybean fields this year, along with the perennial challenge of waterhemp and other weeds prone to herbicide resistance. Spreading those weed seeds only makes control more difficult next season. 

Start with a clean slate

Knowing this, fall becomes a powerful window to apply chemistries that set the stage for cleaner fields next year. 

What many growers may not realize is that colder temperatures slow microbe activity, which means residual chemistries may be less effective. For broadleaf perennial weed species like Canada thistle, the best course of action may be to use systemic chemistry in the fall.

For specialty growers, applying residual herbicides after trees go dormant but before the first frost (in frost-prone areas) helps avoid crop injury while reducing weed pressure the following season. It’s especially beneficial in high-density orchards and systems with shallow root zones, where weeds compete aggressively for limited water and nutrients.

It’s also important to note that winter annuals can serve as hosts for insects and diseases, making late-season scouting even more valuable for specialty crop and row crop growers alike. 

If you let those weeds go unchecked, you’re not just creating a weed problem — you could be creating a host environment for overwintering pathogens or pests. To help, keep track of which fields have issues and where in the field it’s most noticeable, says Ernst. “Doing so helps inform your plan of attack for next year.”

The key to effective late-season scouting is not just identifying where weeds are present, but asking the right questions about why they broke through your program in the first place. 

If a field has escapes, take time now to mark those areas and record the suspected cause. 

• Was it a sprayer miss? 
• Were you using the right chemistry? 
• The right adjuvant? 
• Was the weed too tall at the time of application? 

Evaluating these things can help you make better choices moving forward. 

In addition, assess problem areas to determine the source of failure. If weeds are popping up across an entire field, the likely culprit is a mismatch between the herbicide program and the weed species present — or a resistance issue. If only certain rows or zones show escapes, look at equipment calibration, adjuvant rates or timing inconsistencies. 

Ernst also stresses the importance of making every pass count, including fall applications and mode-of-action diversity. “It’s about having a crop plan, not just kind of making it up on the fly,” says Ernst. “Each field has its own problems, so each field should have its own solutions to those problems.”

Prepare for 2026 now

Looking ahead, Ernst encourages growers to do one final scouting pass. If certain areas struggled with a specific weed species, consider adjusting tank mixes or application timing next season. 

Ernst noted that every season is different, so what worked this year might not work as well next year. But if you observe what didn’t work now, you can make better-informed choices in the future.

Fall weed control also buys growers time during unpredictable spring conditions. If wet soils or high winds delay your first spring application, putting fall herbicide programs in place can provide a cushion. 

“A fall residual is a pretty good idea in drier climates,” Ernst says. “It hangs out all winter, and then when the snow melts, it gets activated. It’s ready to go in the spring to prevent those early-season weeds, especially if we don’t receive moisture right away.”

Ultimately, “Gaining the optimum ROI from your weed control program — regardless of time of year — is about being intentional with what you’re spraying, where, and making sure you’re creating the best program, featuring the best active ingredients,” Ernst concludes. “And combine these strategies with a locked-in game plan for each field.”

Strategic scouting now can drive better weed control decisions next season. Learn more at Wilbur-Ellis or contact your local Wilbur-Ellis location to get the most from your input investment to help maximize ROI this season and next.