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By Staff | Sep 15, 2017

I have two soybean fields that are 10 miles apart. I noted curling attributed to Dicamba in the first field in late July. Just part of the field was impacted which suggested the direction that it had come from. I do not believe that it had come from direct drift. More likely the pattern in the field suggested it had moved there after volatilization. The plants were showing stress from the herbicide but it had a modest impact. Today the plants have metabolized the herbicide and new growth doesn’t show curling. I would expect little/no yield impact.

Recently driving by my other soybeans, they did not look right either. There were signs of cupping in that field too. The neighbor’s soybeans on the other side of the road looked worse than mine and I followed them a half mile to where there were beautiful looking soybeans in the next field that showed no Dicamba damage. The soybeans directly on the other side of the fence line from the great looking soybeans were fried pretty good so the healthy-looking soybeans stuck out as obviously Dicamba resistant and likely the source of the spraying. I took a picture of the fence-line to show the stark contrast in the condition of the soybeans on each side. This Dicamba field was a half mile away from me. The soybeans of the neighbor on the other side of my farm looked worse for Dicamba too than mine but that damage would have had to come from a different source.

The bottom line is that I have fields 10 miles apart that showed evidence of Dicamba and this stuff is moving all over the place. Volatilization appears to be a real serious problem and I really don’t like to see my soybeans curl or to have to investigate which neighbor was responsible. This will be a source for sore feelings in the neighborhood. The running total so far is that 3.1 mln acres of soybeans have been impacted by Dicamba in 16 states. That far understates the extent of the damage however, because that is only the soybeans reported to state regulators and most farmers will not call them. The impact to my soybeans did not appear to justify it but if I had the damage that the neighbor across the road did, I would have made the call.

The Dicamba story made the Washington Post. “The new formulations of Dicamba were approved on the promise that they were less risky and volatile than earlier versions.

“Critics say that the approval process proceeded without adequate data and under enormous pressure from state agriculture departments, industry groups and farmer associations. Those groups said that farmers desperately needed the new herbicide to control glyphosate-resistant weeds. The new Dicamba formulations were supposed to attack those resistant weeds without floating to other fields.

“But during a July 29 call with EPA officials, a dozen state weed scientists expressed unanimous concern that Dicamba is more volatile than manufacturers have indicated. Field tests by researchers at the Universities of Missouri, Tennessee and Arkansas have since found that the new dicamba herbicides can volatilize and float to other fields as long as 72 hours after application.

“Regulators did not have access to much of this data. Although Monsanto and BASF submitted hundreds of studies to the EPA, only a handful of reports considered volatility in a real-world field setting, as opposed to a greenhouse or a lab, according to regulatory filings. Under EPA rules, manufacturers are responsible for funding and conducting the safety tests the agency uses to evaluate products.

“And although pesticide-makers often supply new products to university researchers to conduct field tests in varied environments, Monsanto acknowledged it did not allow that testing on its commercialized dicamba because it did not want to delay registration, and scientists said BASF limited it.”

Monsanto claims that the stuff stays put if applied according to the label and are sticking with that story. My take is that if the stuff is that touchy relative to the parameters of the restrictive label then it will be hard to comply with in the real world of application and risk. This has turned out to be another “whoops!” for seed and chemical companies.

What about next year? The EPA is now discussing an early season cutoff date for use of Dicamba. That will narrow the window under other labeled restrictive conditions for use. Are we all supposed to be forced into buying Dicamba resistant soybeans? The seed and chemical companies would love that, getting rewarded for the damage they caused. Were there instances of operator negligence – probably, but the label is as much a legal document as it was operational instruction. Commercial applicators and insurance companies are not going to want to deal with the liabilities.

ISU Agronomist Bob Hartzler concluded after working to get a handle on the extent of the damage, “I have come to the conclusion that it is not manageable. How can they keep a product this volatile on the market even if it does a great job killing weeds if is this prone to move?” That would be my conclusion too. If the stuff is this touchy to cause this much movement from where it was applied to surrounding fields in conditions that I do not believe caused direct drift, it is too volatile. It is theoretically a great herbicide program but if they can’t keep the stuff where it belongs it is not going to work.

David Kruse is president of CommStock Investments Inc., author and producer of The CommStock Report, an ag commentary and market analysis available daily by radio and by subscription on DTN/FarmDayta and the Internet.

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