When your goal is clean fields, it’s important to have a plan in place to reach that goal. With a weed management plan, you can adapt more easily to unexpected challenges with product availability, weather or equipment.
“It’s better to have a plan than a goal,” says Kevin Johnson, field scientist, Corteva Agriscience. “The goal will always be to have weed-free fields, but how are you planning to reach that goal?”
Here are four weed management strategies that you can implement to improve the effectiveness of your herbicide program:
- Control weeds early. “The easiest weed to control is the weed that never emerges,” Johnson says. “After that, the smaller the better.”
Start with an effective preemergence residual herbicide and plan to use a layered residual in each postemergence pass.
- Scout fields frequently. “Frequent scouting is key to timing your postemergence applications so you can catch 2- to 4-inch weeds instead of fighting 6- to 8-inch weeds, which are much harder to kill.”
Johnson says it’s better to apply layered residual postemergence herbicides early.
“Even if no weeds have emerged — and you have a program that relies on layered residuals — you can still make your application,” he says.
- Use multiple, effective modes of action. When it comes to selecting herbicides to include in each pass, it’s important to think about how many effective modes of action are in your program.
“If you have glyphosate-resistant waterhemp, and you only include Roundup and Enlist herbicides in your program, then you are putting 100% of the pressure on Enlist herbicides to take care of the waterhemp,” Johnson says. “However, if you adjust the mix to Enlist and Liberty herbicides, then you have two effective modes of action working against that weed.”
Liberty® herbicide is the primary tank-mix recommendation with Enlist One® herbicide for acres with high pressure of glyphosate-resistant broadleaf weeds, especially Palmer amaranth, waterhemp and kochia.
- Think long-term. Keeping weeds from going to seed and proactively mitigating the spread of resistance is your best defense for long-term weed management. “Don’t try to save a penny today on weed control, because it will cost you a dollar next season,” Johnson says.
In addition to selecting powerful herbicides each season, the following factors can influence the success of your weed management program:
- Tillage
- Seeding density
- Herbicide application timing
- Harvest (avoid running a combine through areas with heavy weed infestations)
- Fertility programs
- Crop rotations (this allows for modes of action to be rotated, as well)
- Cover crops
Measuring Success in Weed Management
With several factors that contribute to the efficacy of herbicide programs each year, it can be challenging to evaluate how well your program performed compared with previous years.
“You may have dialed in the perfect herbicide program for a field, but unpredictable weather conditions prevented exceptional results,” Johnson says. That’s why he likes to refer to the quote “Are you better today than you were yesterday?” — or, in this case, are your weed control measures better today than they were yesterday?
Frequently evaluating your weed control program and looking for ways to improve the efficacy is imperative to your operations’ success. Work closely with your local retailer and Corteva Agriscience representatives, as they can use their experience with other operations to help determine which herbicide programs and practices will provide improved weed control on your acres.
Enlist Duo® and Enlist One® are not registered for sale or use in all states or counties. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your area. Enlist Duo and Enlist One herbicides are the only 2,4-D products authorized for use with Enlist® crops. Consult Enlist herbicide labels for weed species controlled. Always read and follow label directions. ®Roundup is a trademark of Bayer Group. ®Liberty is a registered trademark of BASF.