Dicamba Rules Vary by State

Another Patchwork of State Dicamba Rules Emerging for 2019

Emily Unglesbee
By  Emily Unglesbee , DTN Staff Reporter
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Dicamba applications will differ state to state again next year, as state regulators race to add new restrictions to the federal labels released in October. (DTN photo by Pamela Smith)

ROCKVILLE, Md. (DTN) -- Pick a state, any state, and chances are the rules for dicamba use there could differ from its neighbors next year.

EPA released federal labels for XtendiMax, Engenia and FeXapan on October 31, and already, a patchwork of additional state restrictions is developing.

Arkansas is weighing a May 20 cutoff date, with large protective buffers for certain sensitive crops. Indiana and Minnesota have both submitted 24(c) special local needs labels to EPA with proposed June 20 cutoff dates. South Dakota has submitted a 24(c) for a June 30 cutoff date, which North Dakota is also considering, and a handful of other states are considering additional steps such as new record-keeping rules and state-specific training requirements.

Whether EPA will approve these state restrictions remains uncertain, however. Recently, the agency has told state regulators that it does not want states to use 24(c) labels to create restrictions beyond federal pesticide labels, because the practice may not be legally sound. (See the DTN story here: https://www.dtnpf.com/…).

So far, only four states have confirmed that they are not pursuing any additional state restrictions on the three dicamba herbicides in question. Missouri announced in a news release in early December that its applicators will follow the federal dicamba labels. Representatives from the Mississippi Department of Agriculture and Commerce, the Illinois Department of Agriculture and the Nebraska Department of Agriculture told DTN that they will not be pursuing 24(c) label restrictions either.

Here are the latest details on state restrictions in development:


On Dec. 6, the Arkansas State Plant Board voted to restrict dicamba use from May 21 through October 31. Applications made before May 21 would require a one-mile buffer around research stations, organic and specialty crops, and crops that are not tolerant to dicamba. The new regulations still have to undergo a 30-day public comment period and a public hearing, before being approved by the state legislature and the governor.

But if passed, this regulation would likely increase dicamba use in the state next year. In 2018, Arkansas banned all in-crop use from April 15 through October 31, but still received about 200 dicamba injury complaints.

The Plant Board heard a presentation from Jason Norsworthy, an Extension weed scientist with the University of Arkansas, who showed university data suggesting that volatility of the new dicamba formulations is the primary culprit in off-target dicamba movement.

"I contend today ... that it's the atmospheric loading of dicamba, especially in areas where we've had heavy use of that herbicide, that has contributed to the landscape damage, and it's a function of volatility that we are ultimately dealing with," he told the board.

The original petition for dicamba use in 2019 was brought to the Plant Board by a group of farmers who requested a June 15 cutoff date. The change to May 21 caught some farmers by surprise, noted Charles Williams, a Crittenden County, Arkansas farmer. "I don't think it's a workable solution," he said.

The May cutoff date may give some farmers "the illusion of choice" now and encourage them to buy Xtend seed, only to find they can't get into the field to spray before that date, he said. "I just wanted a decision up or down on the technology," he said.

Jimmy Williams, who grows berries and produce in northeast Arkansas, said the May cutoff date won't protect a lot of early-season crops. "This year, we started picking strawberries on May 15, and it was already 80 degrees -- and then rose to 90 degrees within a week," he said. "It's too late to be used safely."


Indiana pesticide regulators have submitted a 24(c) label to EPA with a late June cutoff date, based on the recommendations of a work group appointed by the Indiana Pesticide Review Board.

"In order to allow for use without causing unreasonable adverse effects on the surrounding environment, applicators must not apply dicamba post-emergent to soybeans after June 20, 2019," the Office of the Indiana State Chemist reported on its website.

Frustrated by ambiguous language on the labels, the regulators are also adding their own definitions to the 24(c) label: "The work group recommended that the terms "neighboring" and "adjacent" used on the labels shall mean any non-dicamba-tolerant soybeans within 1/4 mile and any other sensitive crop or sensitive residential-area plants within 1/2 mile downwind of the application site."

See more details on Indiana's dicamba use in 2019 here: https://www.oisc.purdue.edu/….


Likewise, the Minnesota Department of Agriculture confirmed on Monday that it is submitting a 24(c) label to EPA with a June 20 cutoff date, which the agency credits with limiting off-target dicamba damage in 2018.

"The decision follows the MDA's ongoing investigations and informal surveys into reports of crop damage from alleged dicamba off-target movement over the past two growing seasons," a department press release stated. "In 2017, the MDA received 253 reports of alleged dicamba drift; 55 of those were formal complaints requesting investigations. Those reports impacted an estimated 265,000 acres. After state restrictions were put in place for the 2018 growing season, the number of complaints dropped dramatically this year to 53 reports, of which 29 were formal complaints. Just over 1,800 acres were impacted in 2018."

Last year, the MDA also banned applications when temperatures rose above 85 degrees, but the agency will not be adding that restriction to the 2019 label.


The South Dakota Department of Agriculture has submitted a 24(c) label to EPA with a June 30 cutoff date, confirmed Tom Gere, agronomy services program manager for the agency.

At a meeting of state regulators in Arlington, Virginia, in early December, Gere said the agency struggled to enforce the R1 growth stage cutoff in 2018 and limit late-season spraying. For 2019, the new dicamba labels ban applications beyond the R1 growth stage or 45 days after planting, whichever comes first.

"Last year in 2018, South Dakota ran with the federal label and we really pushed hard on the R1 stage [restriction], but looking at our stats, the majority of our sales that we've looked at for the last two years resulted in applications that were made after July 1," Gere told EPA.


The North Dakota Department of Agriculture is also weighing a 24(c) label with a June 30 cutoff date, although they have not yet submitted it to EPA, said Jerry Sauter, an environmental scientist with the agency. The state had that cutoff date in place last year, and it shouldn't limit growers' options too drastically, Sauter said.

"If you plant soybeans late, the June 30 cutoff will apply, but for most people, that 45-day post-planting window [on the federal label] will be closed by then," he said.

The agency hopes to have its state requirements for dicamba use finalized by the end of the year, added Eric Delzer, director of the agency's pesticide and fertilizer program.


A handful of states are forgoing cutoff dates, but are working to add additional uses or requirements, either via 24(c) labels or new state regulations, said Dave Scott, pesticide program administrator for the Office of Indiana State Chemist.

On a conference call with state regulators and the EPA, a representative from the Texas Department of Agriculture said it is considering a 24(c) label that would extend the 60-day post-planting application restriction for cotton to 90 days, Scott said. The agency is also considering a state regulation that would address state dicamba training requirements.

Likewise, Iowa, Georgia and North Carolina regulators mentioned on the call that their agencies would be pursuing 24(c) labels to specify state training requirements. Kentucky regulators added on the call that they are considering state regulations that would require additional record keeping for all dicamba products, not just the three new formulations, as well as a new fine structure for pesticide violations.

Finally, the Alabama Department of Agriculture and Industries is planning to pursue a 24(c), that would likely require mandatory state training through the agency and the Alabama Cooperative Extension Service, said Tony Cofer, a pesticide director with the state agency.

State regulators from Illinois had not responded to DTN's inquiries at the time of publication.

See more about state regulators' reactions to the new federal dicamba labels here: https://www.dtnpf.com/….

Emily Unglesbee can be reached at Emily.unglesbee@dtn.com

Follow her on Twitter @Emily_Unglesbee


Emily Unglesbee