On June 3, 2020, the United States Court of Appeals for the Ninth Circuit vacated the federal registrations for the dicamba herbicides Engenia, FeXapan, and XtendiMax. In a June 8 press release, the Environmental Protection Agency (EPA) stated that growers and commercial applicators may use existing stocks that were in their possession at the time of the ban on June 3.
The use of any of these products may not continue after July 31. The federal registration for Tavium is NOT impacted by this decision.
Basically, Bayer, BASF, and Corteva have stopped shipping these products to retailers for distribution. Growers must use what is in their possession according to the previously approved label through July 31.
For those who haven’t planted soybeans, we shouldn’t rely on dicamba products in any preplant burndown unless you have enough on hand or pigweeds have already emerged. If your dicamba supply is limited and weed pressure is light, it would probably be best to save it for an over the top application. Again, Tavium was not affected in this court decision, but double crop soybean is restricted on this label.
Continue with your burndown program with products like Gramoxone, Roundup, or Sharpen. Glyphosate plus clethodim has provided good activity on existing grass weed pressure. Verdict would be a good preplant option since it has burndown activity plus residual control of many of our small-seeded broadleaves and grass weeds. Using Boundary, Anthem Max, or Zidua are our best preplant/preemergence options for Palmer that hasn’t emerged.
If soybeans are up and you’re still within the application window of R1 or 45 days from planting, then I would suggest proceeding with the dicamba application as planned if you have it available, plus a residual. Tavium has a slightly shorter application window, up to V4 or 45 days after planting. Dicamba is currently our “best” option for pigweeds.
If pigweeds begin to recover from this application, many of the Group 14 herbicides like Flexstar GT, Reflex, or Prefix would be good postemergence options, applied within 10 days after dicamba.
Keep in mind that these fomesafen-containing products have a 10-month plant back restriction to corn, so as we approach July it may be a good idea to switch to Ultra Blazer as an alternative. Be sure to consult all labels for use rates and any restrictions.