Iowa weed scientist says dicamba injury was ‘most extensive’ in 2020
July 11, 2020 By Ken Anderson Filed Under: Crops, Crops, Iowa, News
Iowa State University Extension weed scientist Bob Hartzler says dicamba injury this summer is the most extensive he’s ever seen.
Hartzler says reports from
agronomists across the state indicate nearly all
non-dicamba-tolerant soybeans are showing symptoms characteristic of
“And it’s from fence-row to
fence-row in those fields,” Hartzler says. “So you can’t see where the source
came from as the injury dissipates as you move across the field—and that’s the
type of injury we’ve never seen before.”
Hartzler thinks several
factors contributed to the increase in dicamba damage, including confusion over
the Ninth Circuit court decision, this summer’s environmental conditions, and
increased dicamba use on corn.
“The two big things I think
happened is that because we got the corn and beans planted so quickly, that
both corn and soybean fields were being sprayed with dicamba at the same time.
That normally doesn’t happen—and so, collectively, we had more dicamba being applied
in a very narrow timeframe than we’ve ever seen in the past.”
Hartzler says it still hard to
say if yields in injured fields will be impacted.
“In a lot of fields, probably
the majority of the fields, the yield is not going to be impacted,” he says. “But,
in my mind, that’s still not a reason to say, ‘this is okay.’”
Hartzler says it’s hard to
predict what will happen with re-registration of the dicamba products later
this year. But he says new formulations of dicamba with lower volatility than
current products are being evaluated and are projected to be in the marketplace
in the future, pending regulatory approvals.
“Those need to be carefully
evaluated and see if they really do solve this problem with volatility—and if
they are, then let’s get them on the market and replace what we’re doing there.”
Hartzler says significant reductions in volatility and better drift management practices could greatly reduce risks associated with dicamba. And he says the new formulations should also be mandated for use on corn.
Link to blog post by Bob Hartzler and Prashant Jha
Your email address will not be published.
Subscribe for our newsletter today and receive relevant news straight to your inbox!