Rethinking Weed Control in 2022
“We need to prevent failure in 2022, because we don’t have a lot of options to clean up our mistakes,” said Dr. Bryan Young, Professor of Weed Science at Purdue University.
Dr. Young’s advice at a recent Helena training event perfectly sums up the state of weed management this season. When the herbicides we’ve come to depend on are in short supply or simply too expensive, we have to start early and maintain control in different ways. Helena has tips to help you create a flexible herbicide program and manage an uncertain market.
First, set the stage with a solid burndown program followed by a pre-emergence application behind the planter. That should be reinforced with an early post-emergence application that provides both contact and residual activity. Over the years, we’ve relied on glyphosate to clean up anything that got past our pre applications. Since most of the concern today is around post applied herbicides like glyphosate or glufosinate, there is a lot of value in focusing on soil-applied residual herbicides more. Continuing to layer these residuals throughout the season will be key in maintaining control and reducing the potential for resprays. It will also give you the flexibility to use your valuable post herbicides on the acres that really need it. Finally, plan to go back at the end of the season with a post-harvest burndown to reduce the weed seed bank for the following season.
Experts agree that while these supply challenges and price increases continue, it will be necessary to have a plan A, B, C and even D. A great way to do this is to focus on the function of the actives. Continuing with glyphosate as an example, what are the other post herbicides that can get the job done? In broadleaf crops like soybeans and cotton, clethodim is a great option for grass control, and fomesafen can provide excellent residual activity on broadleaf weeds. In corn, HPPD inhibitors like tolpyralate can provide significant control of grass and broadleaf weeds. S-metolachlor is a versatile option, providing residual control of grass and broadleaf weeds in several crops, including corn, cotton, peanuts, soybeans and more. When choosing alternatives, Dr. Young warns us to not lose sight of resistance.
“Herbicide resistance doesn’t go away just because you don’t have available herbicides, or herbicide costs have increased,” said Dr. Young. “Be cognizant of resistance that continues to evolve as you look for alternatives. They might have been alternatives a few years ago, but do they still work today?”
Utilizing multiple modes of action will help manage resistance in addition to broadening your weed control. Once you’ve chosen your herbicides, be sure to use the full labeled rates and pair them with the appropriate adjuvants to improve efficacy. Now’s not the time to hold anything back. Refer back to our previous article on weed control in 2022 for more ways to ensure you get everything you can out of your applications. If there’s ever been a good time to rethink your herbicide program, it’s this season. Contact your local Helena representative for help creating your custom plan.