A Planned Strategy Fights Resistant Weeds

Discovering weed escapes at harvest can be a yield loss nightmare, but the impact of these escapes starts much sooner. Yield loss starts with early emerging weeds that go unchecked. That’s why it’s important to have an effective and proactive herbicide plan in place to stop weeds before they have a chance to establish.  

“It’s important to get it right from the start,” said Josh Putman, Technical Marketing Manager at BASF.  “Preserving your corn yield potential starts early with a foundational pre-emerge herbicide program, like Surtain^Ô herbicide, and layer residual in post applications.”

That foundational program needs to include a front-line, broad-spectrum herbicide. A wide window of application allows you the flexibility to control a variety of tough weeds that can rob you of precious yields.

“Starting clean and staying clean is crucial to preserving yield. Once corn emerges, it’s important to choose an effective broad-spectrum herbicide, like Status^Ò herbicide, to control later-emerging weeds before they get out of control,” said Putman.

Early-season weed control is important. The critical, weed-free period in corn is emergence (VE) stage to the six-leaf (V6) stage. Even a small six-inch weed can cause up to 7% yield loss in corn, if left uncontrolled.¹ Keeping fields clean to canopy closure allows your crop to maximize the nutrients in the soil, water and sunlight without weed competition, maximizing yields. By using a planned, early herbicide application, you can eliminate the weed competition and give your corn a chance to establish a healthy stand. 

“Getting a healthy, weed-free corn stand sets you up for the rest of the year,” said Putman. “Early planning and proper herbicide applications are all key to managing weeds and preserving crop yields.

“Early planned applications are far more effective than late rescue treatments. Much of the damage has already been done at that point.” By tackling weeds early, you are attacking them when they are at their weakest – before they emerge.

“As you’re developing your plan, work with your BASF representative,” said Putman. “They can help you build a program that includes a pre-emergent followed by a post-emergent product with strong residuals and uses different sites of action in herbicides to control resistance.”

Switching up site of action and diversifying your weed management program is crucial to effectively control resistant weed species in the field. Focusing on this now will help to reduce the weed seed bank and preserve existing chemistries.

“Start by pairing a novel pre-emerge herbicide, like Surtain herbicide, that delivers strong residual control of broadleaf and grass weeds and follow it with an early-post application of Status plus Zidua^Ò SC herbicides to manage weeds later into the growing season,” said Putman.

There are many factors that go into managing weeds. One example is choosing the right application rate for managing dense weed canopies and helping to mitigate resistance.

“Larger weeds may require higher application rates due to the increased number of growing points that need controlled,” said Putman. “Herbicide-resistance, especially HPPD-resistance, continues to grow across the country.

“In the case of resistance, spraying higher rates doesn’t necessarily help control resistant biotypes,” said Putman. “In fact, it might be escalating the problem.”

Following the best use practices for a particular herbicide and rotating sites of action help us protect the product we have for future use. 

Status herbicide has a unique combination of two sites of action – dicamba (group 4) and diflufenzopyr (group 19) for enhanced weed control and resistance management. The diflufenzopyr synergizes dicamba, which moves and locks the dicamba active ingredient at the growing points, resulting in fast knockdown. In addition, Status herbicide has proven crop safety so you can focus on killing weeds and not worry about damaging your corn.

Used as a front-line post application, Status herbicide takes down HPPD-resistant weeds effectively, minimizing the need for a rescue treatment. If you’re battling HPPD- and/or glyphosate-resistant waterhemp and Palmer amaranth, Status herbicide provides powerful control without contributing to the overuse of group 27 herbicides. The addition of Zidua SC herbicide extends residual control late into the growing season. 

BASF representatives are available to assist you with keeping your fields clean from start to finish. To learn more about how you can diversify your weed control program and prevent the spread of resistance, talk to your local BASF technical representative or retailer.     

_{¹Knezevic, S. (2015). The critical period of weed control in corn. CropWatch. https://cropwatch.unl.edu/critical-period-weed-control-corn}