As instances of dicamba exposure in soybeans have increased recently, University of Illinois weed scientist Aaron Hager believes the number of affected acres will continue to increase.
However, Hager noted there appears to be some confusion about symptoms of dicamba exposure compared to leaf symptoms caused by nondicamba factors. In the latest crop and pest Bulletin, Hager said dicamba exposure involves several collective symptoms. They include:
- Extreme cupping of trifoliolate leaves, especially upper trifoliolates.
- Veins of affected leaves tend to assume a parallel orientation instead of the usual net venation pattern.
- Tips of cupped leaves with parallel veins are often brown or cream-colored.
- Plants are stunted and may sometimes remain stunted the remainder of the season.
- Depending on time and dose of exposure, pod development can be adversely affected.
“When dicamba is applied in a state that grows soybeans, the occurrence of off-target symptoms is not a question of ‘if,’ but rather ‘scale.’ Some suggest the solution is to plant all soybean acres to dicamba-resistant varieties. That might solve issues associated with soybeans, but would likely increase the incidents of damage to other dicot species across the Illinois landscape,” Hager noted.
Jeremy Wolf, a Homer farmer, said he has experienced damage to his soybean fields from neighboring ones where crop protection products that included dicamba had been applied.
“When you pour your heart and all of your effort and time into producing a crop and then you walk in and you find damage, it’s upsetting. It makes your heart drop,” said Wolf, of Champaign County. “It’s the situation we’re in, and we just want to learn as much as we can about this while we have this opportunity.”
Related: Don’t let dicamba take over your weed-management plan. Click here.
John Haase, a Mount Carmel farmer, said he planted Roundup Ready 2 Xtend soybeans on fields isolated from neighboring nonresistant soybeans and homeowners.
“We want to keep the technology, but people plant different varieties of beans and other sensitive crops. We’ve got to keep those people in mind, too,” Haase told the RFD Radio Network®.
The Wabash County farmer bought recommended spray nozzles last winter and paid close attention to wind speed and direction before spraying.
In an interview with FarmWeekNow.com Wednesday, Hager continued to stress the need for careful stewardship related to new crop-protection products that contain dicamba.
“There’s not a thing wrong with the technology, but people have to understand, this is dicamba,” said Hager. “We’re not seeing anything that we haven’t seen before. Why did we ever think we were going to spray more acres of dicamba in Illinois and not have issues with it? That goes against 50 years of experience. Are we going to continue to have issues with it in the future? Certainly.”
To read more from Hager on “The Dicamba Dilemma in Illinois: Facts and Speculations,” go to this link.
Some parts of Illinois may still be in the #spray17 window. For more information, go to ilfb.org/steward.
Content for this story was provided by FarmWeekNow.com.