What the New Dicamba Label Looks Like in the Real World

Late Tuesday afternoon, EPA announced it approved three dicamba formulations for over-the-top use for five years, 2021 through 2025. The formulations included are BASF’s Engenia, Syngenta’s Tavium and Bayer’s XtendiMax.

“The five-year component is huge because it gets rid of uncertainty,” says Jim Hedges, vice president of seed for Winfield United. “You know [2020] caused a lot of anxiety amongst growers and our owners, ag retailers. So, having this stability within the trait platform, as we start to transition from Xtend to XtendFlex is great.”

This five-year unconditional registration varies from previous approvals in length and conditions. It did, however, list changes to the label that must be followed by applicators. As a reminder, these changes include:

• Downwind buffer of 240' is required and a buffer of 310' required where listed species are located. The previous label buffer was 110’ for downwind.
• Over-the-top application of dicamba of soybeans prohibited nationwide after June 30, and after July 30 in cotton.
• An approved pH buffering agent will be required to be mixed for application to lower volatility. Buffering agents are registered with the EPA and must be documented each use.
• Opportunities for growers to use hooded sprayers to reduce buffers.
• No more 44 oz. rate option.

"All of these efforts will help ensure there are not negative impacts on other farmers' lands," says Andrew Wheeler, EPA administrator. "States can further restrict, but they have to work with us and file the appropriate requests with EPA. We're trying to have a national program here, we're responding to the court's concerns with a national cutoff."

Implications for applications.

Bayer and BASF have each created their own buffering agent to help reduce volatility. They’re required tank-mix additives.

“VaporGrip Xtra [Bayer’s buffering agent] works in two ways, the first is to control that pH solution,” says Alex Zenteno, Bayer dicamba product manager. “The other is the VaporGrip technology attaches itself to available protons in a solution to prevent the formation of the dicamba acid.”

So far, each product has been tested on a smaller scale, which leaves some to wonder how effective they’ll be in real-world conditions.

“We’ll have to wait and see how effective volatility reducing agents are,” says Bob Hartzler, Iowa State University Extension weed scientist. “I’m aware of their tests on relative small-scale studies and I think it’s hard to ramp up when you start spraying large acreages.”

In addition, the label now has a national spray cutoff—June 30 for soybeans and July 30 for cotton. EPA officials said they believe this move addresses some concerns outlined by the 9th Circuit Court of Appeals.

“I don’t think universal dates work,” Hartzler continues. “I don’t see how the date that works for Iowa would be appropriate for Arkansas. June 30 is probably about as good as you could hope for in Iowa.”

There might be opportunities for states to create local changes to the label, including cut off dates. In the past states have added further restrictions and this coming year could see more of the same, or the potential for request for a broader application window. States have to work with EPA to enact any changes.

The last big change is to downwind buffer requirements. Previously, EPA required a 110’ bugger for 22 oz rates and a 220’ buffer for 44 oz. rates. There will be no more 44 oz. option and the downwind buffer more than doubled to 240’ with this new label.

Like with previous labels, if a sensitive crop, including non-Xtend soybeans or cotton, is downwind, farmers and applicators should not spray dicamba. In areas with endangered species a 310’ downwind buffer and 57’ border buffer is required.

“Let’s give these changes a year or two and see if they’ve minimized problems we saw in the first four years,” Hartzler says. “If they dramatically reduce them, I say let’s keep going. But if we see similar problems we saw through 2020 I think [over-the-top dicamba] needs to be reevaluated. How much can you tweak the label?”

Keep tools in the toolbox.

Industry and some farmers have praised EPA for this decision as it keeps yet another tool in their toolbox in the fight against resistant weeds.

“We need that mode of action out there,” says Nick Ehlers, farmer from eastern Iowa. “Let’s see guys do a wonderful job of spraying it. We need a mode of action with residual that waterhemp and pigweeds can’t break through.”

Ehlers notes that some farmers in his area don’t always follow label directions exactly—a practice he implores them to stop. With new label changes, and ‘simpler’ terms added to new new label that is half the size of the 2018 label, he hopes they will.

“The need for Engenia herbicide is greater than ever before due to increased weed resistance,” Scott Kay, Vice President of U.S. Crop, BASF Agricultural Solutions said in a news release. “Controlling resistant weeds is not only a physical challenge for farmers, it also can have a significant financial impact. Farmers planting dicamba-tolerant cotton and soybeans could potentially stand to lose more than $10 billion if they lost access to dicamba-based herbicides, like Engenia herbicide.”