Dicamba Details

States Start to Rule on Dicamba

Farmers need to check state labels for additional spray requirements as they head into the coming season. (DTN photo by Pamela Smith)

DECATUR, Ill. (DTN) -- Arkansas farmers will go to the field this spring with a more stringent set of dicamba herbicide spray requirements than those found on Environmental Protection Agency (EPA) labels. Gov. Asa Hutchinson agreed this week to approve the Arkansas Plant Board's proposals to ban some dicamba formulations and place a cutoff date on others, including Monsanto's recently approved XtendiMax with VaporGrip.

EPA recently labeled two lower-volatility formulations of dicamba, XtendiMax and BASF's Engenia, for use in the Roundup Ready Xtend Crop System. Although a few states are still waiting for endangered species assessments and may be added to labeling later, the federal label is complete for most of the core soybean and cotton production states and ready for state action.

Individual states are allowed to adopt additional label requirements for products based upon specific needs or concerns. Calls to state departments of agriculture by DTN found most states are adopting the federal label as is, which contains a long list of spray requirements aimed at mitigating herbicide drift.

Arkansas' move is the most far-reaching as it will not allow sprays of DGA-based dicamba formulations (including XtendiMax) between April 15 to Sept. 15. That leaves Engenia herbicide, a new BAMPA salt, as the only dicamba allowed to be used in-season in that state this year.

Indiana has proposed a rule to make agricultural formulations that contain 6.5% or more dicamba a restricted-use pesticide (RUP). Mississippi has proposed to ratchet EPA's 15 mile per hour (mph) wind spray speed allowance back to 10 mph. In Mississippi, Georgia, Tennessee and Indiana, applicators will be required to participate in special auxin herbicide training. Procedures for making such changes vary between states -- some require action by the governor and others, the state agriculture department.

Although not a labeling consideration, Missouri and several other states are weighing legislation that would increase state fines and penalties for applicators caught violating state and federal labels.

The additional scrutiny comes on the heels of a rash of dicamba drift and damage complaints in the Midsouth and parts of the Midwest during the 2016 season as growers grew soybeans and cotton designed to be used with dicamba, but had no labeled dicamba herbicides to legally use postemergence on those crops. With major seed companies and licensees poised to release additional Xtend varieties, and approved herbicides now in hand, dicamba usage is expected to grow considerably in 2017.

Purdue University weed scientist Bill Johnson told DTN that Indiana's RUP status for dicamba is not likely to wend its way through rulemaking in time for the 2017 season and that the federal label will be followed until a change is made. That's unfortunate, he said, because it increases the chance that generic dicamba might be used in the crop, which could increase the potential for off-site movement.

"It [RUP] makes it easier to track purchases to make sure growers are using the right formulations on their soybeans," he said. RUP pesticides can only be purchased by certified pesticide applicators and records are kept of sales, which help in investigations of misuse.

Illinois Fertilizer & Chemical Association (IFCA) President Jean Payne told DTN that their association supported discussing the possibility of seeking RUP status for all dicamba products in Illinois so that they could be purchased and applied by trained, certified applicators. However, she said meetings with other agriculture groups, industry representatives and the Illinois Department of Agriculture in early December could not reach a consensus to pursue the RUP designation at this time.

"With 10 million acres of soybeans, we will be a large market for this new technology, and as with all pesticide use, IFCA always seeks to be proactive and use common sense tools at our disposal to ensure judicious use of this new technology for agriculture, and also to successfully co-exist with organic growers, non-GMO soybean crops, orchards, vineyards, specialty crops and homeowners," Payne said.

"There are 15,000 licensed private applicators in Illinois (farmers) and 20,000 licensed commercial applicators, so we did not view keeping the use of the technology to these trained applicators as an impediment to access to the product," she added. "The feeling is that trained applicators will better understand the complexities of the label, will keep a record of the application and will consider the agronomic, environmental, societal and legal ramifications for proper use of this product. It's also vital that everyone understands that only the new dicamba formulations can be used over the top of soybeans, not any existing dicamba herbicides that are not labeled for such use, but are readily available and have the active ingredient that will also perform on the Xtend soybeans," she said.

Illinois has decided not to adopt any additional label restrictions beyond the federal label at this time, said Warren Goetsch, bureau chief, Illinois Department of Environmental Programs, in a DTN phone interview. "There's no evidence in Illinois to suggest that a different course of action would be justified," Goetsch said, stressing that he did believe everyone agrees a strong stewardship campaign is needed to communicate label requirements.


The pesticide committee of the Arkansas Plant Board requires manufacturers to provide third-party drift and volatility studies for pesticides to be registered in the state. The additional label proposals sent to Arkansas Gov. Hutchison were based on the fact that Monsanto did not meet that requirement. University weed scientists have also repeatedly stressed that less volatile formulations do not prevent physical drift onto sensitive crops and that EPA does not consider damage to non-target crops when considering whether a pesticide should be classified as restricted use.

Hutchinson said he concluded the proposed rules wouldn't "unnecessarily burden business" as he approved them. He also added:

"However, the methods that are used and the research on which the Plant Board relies in approving new technologies must be more clearly defined in order to provide more certainty to all companies attempting to introduce these technologies in Arkansas. To this end, I am tasking the Plant Board to submit a solution to me within forty-five (45) days, which provides clear rules to industry as to what the Plant Board expects in terms of prior study and testing by independent third party research."

In a prepared statement, Monsanto spokesman Kyel Richard noted that it is positive that Arkansas farmers will be able to experience the Xtend soybean and cotton trait systems with at least one formulated product. "However, it is unfortunate that to this point, the State of Arkansas has not enabled farmer choice by fully approving all of the formulated products the EPA and 24 other states so far have permitted for in-crop use," the statement said.

The company noted that it is vital that all competitors within the industry be able to follow clear and standard guidelines for product evaluations and approval. "To that end, we appreciate Gov. Hutchinson's call for the Plant Board to clarify and standardize what it intends to require for third-party research," said Monsanto's statement.

To read Hutchinson's letter: http://www.dtn.com/…

For more information on Indiana's RUP efforts: http://www.oisc.purdue.edu/…

For more on Arkansas' dicamba restrictions: http://bit.ly/…

Pamela Smith can be reached at Pamela.smith@dtn.com

Follow her on Twitter and @PamSmithDTN