Office of Indiana State Chemist announces 2020 dicamba restriction

Story by Emma Ea Ambrose

November 21, 2019

The Office of Indiana State Chemist (OISC), the pesticide regulatory agency for Indiana, recently announced an additional label restriction for users of the herbicide dicamba.

After careful consideration, State Chemist and Seed Commissioner Robert Waltz has determined his agency will be forwarding FIFRA Sec. 24 (c) special local need registration requests to the United States Environmental Protection Agency (USEPA) for Indiana specific labels for the use of dicamba on soybeans in the 2020 growing season. These state labels will require the following additional provision: Do not apply this product after June 20, 2020.

“The number of off-target complaints received by OISC has continued to rise since the introduction of this herbicide technology on soybeans in 2017, and 2019 was no exception. The OISC is taking state action to reduce those numbers,” said Waltz. “This application cutoff restriction was reached after exhaustive complaint incident analysis by OISC over the last three years, as well as consultation and input from the Indiana Pesticide Review Board and stakeholders in the agriculture industry.”

In addition to the June 20 application cutoff date, OISC will support Purdue University Extension experts in advising Indiana soybean producers about other available weed control options for the 2020 growing season. Similar application cutoff dates and weed control outreach have already been initiated in other major soybean producing states such as Illinois, South Dakota and Arkansas.

“Growers need to be reminded that over reliance on any single weed control option like dicamba, year after year, will lead to premature herbicide resistance,” said Bill Johnson, botany and plant pathology professor and weed scientist. “Weed scientists from across the country support efforts to reduce the potential for possible adverse effects from off-target movement, but we also want to promote efforts to preserve the usefulness of these valuable herbicide tools for as long as we can.”

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