Dicamba - General Information

Dicamba is a highly volatile chemical that can damage non-target plant species through spray drift (particle drift) and/or volatilization (vapor drift). New formulations were designed to reduce volatility. However, since OTT dicamba was registered for use on DT soybeans, the MDA has received complaints for off-site movement onto neighboring property. 

Annual Total Reports for Alleged Dicamba Drift

*No endorsement is implied in the referencing of trade names.

Dicamba is a systemic herbicide that functions as a plant growth regulator. Following application, dicamba is absorbed through leaves and roots of target weeds and is translocated throughout the plant. In the plant, dicamba mimics auxin, a type of plant hormone, and causes abnormal cell division and growth.

Dicamba belongs to the benzoic acid chemical class and is a Site-of-Action 4 herbicide. Other herbicides belonging to Group 4 (synthetic auxins) with a similar mode-of-action include 2,4-D, MCPA, clopyralid, halauxifen-methyl, and aminopyralid.

In Minnesota agriculture, dicamba is used to control weeds in crops including corn, small grain, soybeans, and hay, as well as on fallow cropland, pastures, and land enrolled in conservation reserve programs. In 2016, Minnesota registered three new dicamba products (XtendiMax, Engenia, and FeXapan) for OTT application to DT soybeans to control broadleaf weeds such as pigweeds (Amaranthus spp.), ragweeds (Ambrosia spp.), horseweed (Conyza spp.), and Kochia spp. Prior to 2016, dicamba was registered for pre-plant and pre-emergence applications in conventional soybeans, Roundup Ready soybeans, and Liberty Link soybeans. New DT soybeans are tolerant to dicamba and glyphosate herbicides.

In 2017, the MDA received 249 complaints of off-site dicamba damage. To curb off-site movement, the MDA set June 20 as the annual application cutoff date for registered dicamba products from 2018 to 2020. This date was based on research and pesticide misuse complaints. In October 2020, EPA set June 30 as the application cutoff date on federal labels for OTT dicamba applications to DT soybeans. In 2022, the MDA worked with the U.S. Environmental Protection Agency (EPA) and the registrants of the three dicamba products to include the date and temperature cutoff restrictions on the product labels. On February 6, 2024, the U.S. District Court of Arizona vacated the 2020 federal registrations of OTT dicamba products for soybeans, XtendiMax® (EPA Reg. No. 264-1210), Engenia® (EPA Reg. No. 7969-472), and Tavium® (EPA Reg. No. 100-1623), making their sale or distribution illegal in the United States after June 12, 2024. As a result of the court decision, OTT dicamba products were no longer registered for use in Minnesota in 2025.

Following the 2024 court ruling, the pesticide registrants submitted new product proposals that include OTT application of dicamba on DT soybeans. The revised labels proposed new use patterns and stricter restrictions, including reduced application rates and limited over-the-top use in soybeans, aimed at reducing off-target movement and preventing crop damage. On February 6, 2026, three dicamba products, Engenia® (EPA Reg. No. 7969-507, BASF), Stryax™ (EPA Reg. No. 264-1241, Bayer), and Tavium® Plus VaporGrip Technology (EPA Reg. No. 100-1753, Syngenta) received federal registration and subsequently were registered for use in Minnesota. These products are approved for use on DT soybeans and DT cotton only.

Non-agricultural applications of dicamba include uses on residential lawns and on golf course turf throughout the state. Engenia®, Stryax™, and Tavium® are not approved for these uses.

The MDA tracks the sale of pesticide active ingredients in the state. The graph below shows annual dicamba sales in Minnesota between 1996 and 2024. Dicamba sales data are pooled for all forms of dicamba and reported as the pounds of dicamba acid equivalents (a.e.) sold. Sales data are available through the Pesticide Sales database.

Dicamba has a low acute toxicity via oral, dermal, and inhalation routes. It is an eye and dermal irritant, but it is not a skin sensitizer.

Human Health Values for Dicamba Acid. Data from US EPA_¹ and the Minnesota Department of Health (MDH).

Dicamba toxicity is low for aquatic organisms, mammals, and honeybees, and it is moderately toxic to birds. Non-target plants exposed to dicamba may be damaged by this herbicide.

Dicamba acid toxicity values for aquatic and terrestrial organisms. Data from US EPA²

*ALB value based on toxicity data from US EPA³.

3,6-dichlorosalicylic acid (DCSA) is the major degradate, or breakdown product, of dicamba. Because DCSA is primarily formed in plants, the EPA does not expect DCSA to reach groundwater at levels that would be of concern. However, DCSA is more toxic than the parent compound to certain species of birds and mammals; thus, there could be potential for adverse effects to certain species of birds and mammals. Mitigations are imposed on registration to alleviate these risks. Other minor degradates of dicamba include 3, 6-dichlorogentisic acid (DCGA) and 5-OH-dicamba.

Dicamba product labels include environmental hazard statements and language may vary among products. See individual product labels for full list of environmental hazards and spray drift management restrictions or recommendations. Always read the label before applying a pesticide.