Ralph Lassiter, Enlist field specialist, Dow AgroSciences
When it comes to weed management, growers in the South are like doctors treating patients. Like a good doctor, growers need to diagnose the illness (or weeds) to prescribe the right medicine (or weed control).
It’s important to scout the previous year and know what is going into the field and the crop system you’re planning for the year. This helps determine strategy. If you don’t know what your adversary is, you don’t know what strategy to use. Don’t be reactive when it comes to weed control.
Be proactive with weed management, whether weeds are resistant or not. Scout to know what pests might be in the field. Then, use soil-applied residual herbicides based on what weeds are in the field and plan post applications based on what is available for the weeds you are trying to control.
Glyphosate-resistant Palmer amaranth is prominent in the Southeast, but there are other weeds, such as common and giant ragweed and morningglory, in the fields. We need a program in place that is broad enough to control these other weeds as well.
The Enlist Weed Control System will allow growers to take control of the toughest weeds in their fields, including resistant and hard-to-control species. Enlist corn, soybeans and cotton are tolerant to Enlist Duo herbicide, a proprietary blend of new 2,4-D choline and glyphosate. Regulatory approvals are pending for Enlist cotton.
The two modes of action in Enlist Duo work with a program approach to deliver season-long control and help prevent resistance. Don’t underestimate the importance of overlapping residuals to keep weeds under control.
Each residual herbicide has a life span, but the average is about four weeks. With overlapping residuals, you don’t wait for the first residual to play out, but, instead, you apply a second residual before the first one is completely gone. Then, you’re not behind and there is a constant layer of residual on the field.
During the season, take the following steps to manage weed resistance.
- Start clean. Manage weeds that came up during early spring. If you don’t, you’re behind. Begin with tillage or a burndown and have a clean seedbed.
- Make timely preemergence applications of soil-applied residuals. Consider Sonic herbicide or SurveilCo-pack soybean herbicide, which are effective against primary weeds.
- Scout fields and know when preemergence applications are no longer active. Make timely post applications. For example, use a postemergence application of Enlist Duo herbicide with Colex-D Technology on Enlist crops.
Equipment is another tool in a grower’s “doctor’s bag” when it comes to weed management.
Make sure you have well-calibrated equipment, and take the time to prepare your spray equipment. Confirm that the nozzles are designed for the product you’re applying and the sprayer is calibrated for uniform coverage. If we can’t get the herbicide to the target, we can’t control weeds.
Seed is constantly emerging. A weed’s only survival tactic is to reproduce. We usually do a good job up until canopy and then move on to insect control. But if canopy isn’t closed completely, weeds continue to emerge. They may not get large, but they can put seed back in the ground. Again, be proactive. Eliminate late-season seed production.
For more information on the latest herbicide-tolerant trait technology available to help you manage hard-to-control and resistant weeds, visit Enlist.com or talk with your Dow AgroSciences sales representative.
Trademarks of The Dow Chemical Company (“Dow”) or an affiliated company of Dow. Regulatory approval is pending for Enlist cotton. Enlist Duo, Sonic and Surveil Co-pack are not registered for sale or use in all states. Contact your state pesticide regulatory agency to determine if a product is for sale or use in your state. Always read and follow label directions. 2015 Dow AgroSciences LLC