Monsanto attacks weed scientists who say new 'low volatility' dicamba is still too volatile, hurts crops

Bob Scott, University of Arkansas
(NPR photo by Dan Charles)

Monsanto Co. is fighting back against weed scientists who say its herbicide dicamba is hurting crops, Dan Charles reports for NPR. Monsanto, BASF and DuPont all sell herbicides containing dicamba, as well as seeds for corn and soybeans that are genetically engineered to withstand it. The companies came out with new "low-volatility" formulas in 2016, and have blamed reported crop damage since then on improper application of the weedkiller. But weed scientists say they weren't able to test the products before they hit the market.

"I wish we could have done more testing. We've been asking to do more testing for several years, but the product was not made available to us," University of Arkansas weed scientist Bob Scott told Charles. "These are proprietary products. Until they release those formulations for testing, we're not allowed to" test them.

When scientists were finally able to test the new low-volatility versions, they found that damage to nearby crops didn't come from physical drift--windblown droplets of dicamba--but from volatization, the chemical's propensity to turn into a powder and drift elsewhere.

"In Arkansas, where state regulators proposed a ban on dicamba during the growing season next year, Monsanto recently sued the regulators, arguing that the ban was based on 'unsubstantiated theories regarding product volatility that are contradicted by science,'" Charles reports. "The company called on regulators to disregard information from Jason Norsworthy, one of the University of Arkansas' weed researchers, because he had recommended that farmers use a non-dicamba alternative from a rival company. Monsanto also attacked the objectivity of Ford Baldwin, a former university weed scientist who now works as a consultant to farmers and herbicide companies."

Kevin Bradley, a professor of weed science at the University of Missouri, says Monsanto executives have repeatedly called his supervisors to express their displeasure with his research on dicamba. Scott says Monsanto's actions are an "attack on all of us, and anybody who dares to [gather] outside data."

Monsanto's Vice President of Global Strategy Scott Partridge told Charles, "We are not attacking Dr. Bradley. We respect him, his position, opinion, and his work. We respect him, and academics in general."

Two weeks ago the Environmental Protection Agency said dicamba use will still be allowed next year, though with additional restrictions. Some say that's not enough, because the restrictions address application, and not the fundamentally volatile nature of the herbicide. Arkansas may ban it at the state level, and will hold a public hearing for the proposal on Nov. 8.