Dicamba

Thank you to the University of Arkansas for the dicamba injury on soybeans photograph.

Please contact the Pesticide State Lead Agency to report Dicamba injury or issues.

2017 and 2018 materials from this Dicamba page have been moved here.


Dicamba-tolerant seeds were registered for use during the 2016 growing season.  Due to the lack of the accompanying dicamba formulation which was required to be used with the seeds, many growers used older formulations and the resulting drift and volatilization issues caused widespread crop damage and enforcement issues.

EPA registered the new dicamba formulation in the fall of 2016.  During the 2017 growing season we continued to see widespread crop damage and enforcement issues.  EPA and the registrants negotiated new labels for the 2018 season.  During 2018 there were still many issues with crop and non-crop damage and enforcement.  EPA approved a conditional 2-year registration with revised labels and requirements for the 2019 and 2020 seasons.


Moving into the 2019 Season

Q&A on the new labels-answers from U.S.EPA:

  1. Will 24 C labels be allowed to make labels more restrictive if a state determines it to be necessary to ensure “no unreasonable adverse effect” from the post-emergent use of these products?

Under the authority of 24(c) of FIFRA, states may register an additional use of a federally registered pesticide product, or a new end use product to meet special local needs. Special local need (SLN) means an existing or imminent pest problem within a state for which the state lead agency, based upon satisfactory supporting information, has determined that an appropriate federally registered pesticide product is not sufficiently available. Because of the unique goals states are looking to accomplish in managing the dicamba over-the-top (OTT) registrations, EPA is requesting that states consult with the agency prior to submitting an SLN for the 2019 season.

2. Does “for retail sale to and use only by certified applicators” mean that applicators who are not fully certified, i.e. registered technicians who have passed only the core/general standards exam, cannot purchase or use these products?

The products may only be purchased and used by a person who is a fully certified applicator. Persons who are not certified applicators may not perform any activities with these dicamba products, including mixing or loading, even if under the supervision of a certified applicator.

  1. Does the training requirements reference to “before applying this product in-crop” suggest that the CRP and noncropland uses are not covered by the training requirements?

Training requirements apply to any use of the product, not just in-crop use.

  1. Application records must include start and stop times. If the wind direction shifts toward neighboring sensitive crops or residential areas, and the applicator stops the application, but doesn’t pick up the application until the following day, is that a separate application or the same one?

Accurate records must be maintained. Each time the certified applicator starts or stops an application it needs to be recorded, regardless of which applicator is performing the application or which day. Certified applicators must comply with the requirements of the states who certify them.

  1. The label states, “DO NOT apply to soils classified as sand with less than 3% organic matter and where groundwater depth is shallow.” How deep is shallow?

EPA intended this label statement to be advisory for states to apply their judgement in training certified applicators and providing oversight on this label section.

  1. The resistance management section states, “the following steps should be followed”, but then states “DO NOT rely on a single herbicide site of action…”  We assume the DO NOT is for effect and not enforceable, correct?

Correct.

  1. The label states, “DO NOT apply XXX later than 45 days after planting or R1, whichever comes first.” Any suggestions on how to document planting date or R1 growth stage 3-8 weeks after application?

These parameters are subject to the applicator reporting. Planting and application dates are items that are subject to the mandatory reporting protocol.

  1. The label states, that non-sensitive crops and areas include, “Roads, paved or gravel surfaces, mowed and/or managed areas adjacent to field, such as roadside rights-of-way.” We assume this means that mowed and/or managed roadsides are no longer to be protected by buffers, correct?

Correct. Including roadside rights-of-way as non-sensitive areas was intended to aid in buffer calculations.

  1. The spray drift management section states, “DO NOT allow herbicide solution to drip, physically drift or splash onto desirable vegetation…” We assume that physical drift excludes off-target movement from volatility, but does “physical drift” include or exclude off-target movement from application into an inversion? Our understanding is that application into an inversion should affect all pesticides equally, regardless of active ingredient, correct?

EPA is looking forward to further discussing this issue and coordinating with the states.

  1. Do the endangered species and corresponding buffer zones apply to all endangered species or just endangered terrestrial dicot plant species, as suggested by BASF?

The buffer requirement was made after we assessed potential risk to both animals and plants that are federally listed as endangered or threatened species. For the full list of species that were assessed in the effects determination document, see the recent and previous assessments:https://www.regulations.gov/document?D=EPA-HQ-OPP-2016-0187-0967. Growers should refer to Bulletins Livefor a listing of Pesticide Use Limitation Areas (PULAs) for endangered species as it relates to dicamba. If a county is listed in the Bulletins Live system, growers in that county must follow the restrictions on the bulletin.

11. The sensitive crops and residential areas section states, “DO NOT apply when wind is blowing in the direction of neighboring sensitive crops or residential areas. The appropriate distance must be determined by the applicator relative to where the application is being made, the environmental conditions, and the potential risk to downwind sensitive crops and residential areas.” What specifically does that mean? It seems very non-specific and vague. It appears that it provides no real direction or instruction to the applicator, rendering it unenforceable? Can the agency provide additional direction on the intent of this statement?

This language is intended to be advisory to growers. At a minimum, certified applicators must not use the product if sensitive crops are directly adjacent to the treated field.


Endangered Species:  On November 19, 2018, EPA posted Dicamba Pesticide Use Limitation Areas.  The county list may be found at: https://www.regulations.gov/document?D=EPA-HQ-OPP-2016-0187-0974


On October 31, 2018 EPA released changes to the Dicamba registration.