BASF on Thursday addressed questions about spreading dicamba drift issues on a media briefing call.
In Arkansas – which is investigating 720 complaints about the herbicide drifting from neighboring farms – Dr. Dan Westburg, BASF technical service manager, observed that in most of the cases he saw, buffer zone guidelines were not followed. The state requires a one-quarter-mile downwind buffer, plus 100 feet on the other three sides of the field, yet Westburg says he saw cases where the buffer was as narrow as a field row or ditch, and at least one case where there was no buffer at all.
Moreover, there was frequently a strong indication that the wrong nozzle was used.
“The one thing I emphasize above all else in making an on-target application is the right nozzle selection. If that’s not done, there is nothing else you can do to improve upon the application,” he said.
He noted that BASF issued more than 600,000 nozzles to applicators in its nozzle giveaway program.
Westburg also saw cases where uniform symptomology suggested some form of tank contamination, as opposed to spray particle drift. However, concrete evidence of this is harder to pin down.
Applications occurring late in the evening or at night during a temperature inversion likely added to the problem. Moreover, the boom height was likely too high in applications done then.
“I think inversions are one of least understood things we’re dealing with from a weather perspective,” Gary Schmitz, BASF technical service manager, said. Not only can droplets can move longer distances, “but movement during inversions can be confused with volatility.”
Specifying that no night-time applications should be made “is maybe a clarity we could add to the recommendations, versus just during temperature inversions,” particularly for parts of the northeast Delta, Westburg said.
He stressed: “I talked to a large number of growers who have had success and had excellent control of Palmer amaranth. They said, ‘We’ve gotten best control of Palmer amaranth that we’ve gotten in 10 years or more.’ The product is being used effectively and on-target, and we’re working through other areas where the restrictions have not been followed.”
Throughout the Corn Belt, Engenia applications were, on the whole, successful in controlling tough and resistant weeds, and without incident, Schmitz said.
More than 10 million acres of soybean and cotton were treated with Engenia this season.
In some of the cases of off-target movement being investigated in the Corn Belt, “it was clear that not all labels were followed, they weren’t using the right nozzles, there was incorrect boom height, or there was spraying during high winds and temperature inversions,” he said.
“BASF is committed to developing fact, science-based recommendations that focus on long-term solutions for farmers. We can only do so once we have further clarity on the ongoing investigations regarding crop responses attributed to dicamba,” Westburg said. The company is working jointly with state regulators, extension weed scientists, consultants, and growers to identify what occurred and “the areas we need to further enhance,” he said.
Schmitz noted that in states where face-to-face training was mandated – including Alabama, Georgia, and North Carolina – it has had fewer complaint calls. BASF will continue to reach out to more growers and applicators via its On Target Application Academy to train on application stewardship over the next several years, he said.