By John Wallace and Dwight Lingenfelter
On June 3, the U.S. Court of Appeals for the 9th circuit vacated the registrations of three dicamba products (XtendiMax, Engenia, FeXapan) labeled for over-the-top use in Xtend soybean systems. After several days of uncertainty, we now have guidance from the EPA about use of these products in the 2020 growing season. Based on the Court’s decision, the EPA considers these products no longer to be registered as of June 3, 2020 but allows for use of existing stocks under limited conditions:
- Use of products: The EPA order allows private and commercial applicators to use existing stocks that were acquired prior to June 3, 2020. Applications of these products are permitted until July 31, 2020.
- Distribution and sale: The EPA order limits further distribution and sales of these products to only existing stocks that were in possession of commercial applicators prior to June 3, 2020 in order to facilitate use of the product by the July 31st deadline.
In light of these recent events, there are few more things to be aware of for the 2020 season.
- Though the July 31st deadline will permit postemergence use of these dicamba products in full-season soybean, keep in mind that the label restricts applications of these products to 45 days after planting or the R1 growth stage of soybean.
- Although it was not mentioned in the ruling, we do not recommend using dicamba as a burndown in double-crop soybeans since it can be risky. At that time of year, many sensitive crops and ornamentals are very susceptible to dicamba and weather conditions favor dicamba drift.
- Tavium, which is a pre-mix of dicamba and S-metolachlor that can be applied up to the V4 growth stage in Xtend soybean, was not part of the ruling and will continued to be sold, though supply is likely to be limited.
- Keep in mind, other dicamba-containing products such as Clarity, Banvel, Status, and the many generics cannot be legally sprayed over-the-top of Xtend soybeans.
- Enlist E3 soybean varieties have not been affected by this lawsuit and thus registered 2,4-D choline products (Enlist One and Duo) can be used in that system. These 2,4-D products cannot be used in Xtend soybean systems, otherwise major crop damage will occur.
We will continue to provide updates on the short- and long-term implications of the Court decision on the Xtend soybean system as more details emerge. We will also provide some alternative soybean herbicide options to consider in upcoming newsletters. The EPA cancellation order
can be read online.