The Deal With Dicamba: An Overview of Dicamba-Related Litigation


Dicamba is a powerful herbicide that has been used for years to combat difficult-to-control weeds such as palmer amaranth, commonly known as pigweed. While dicamba is an extremely effective herbicide, it has problems with volatility, easily becoming airborne and drifting off-target during application. Due to its issues with volatility, dicamba has historically been applied prior to the start of planting in order to kill off weed seeds without damaging crops. However, in 2015 Monsanto Company launched a line of dicamba-resistant soybean and cotton seeds. Following that launch, the Environmental Protection Agency approved dicamba-based herbicides from both Monsanto Company and BASF Corporation for in-crop use.

Since then, hundreds of lawsuits have been filed against both Monsanto Company (which has since been acquired by Bayer) and BASF Corporation for harm caused by dicamba. All the lawsuits filed in the federal court system have been consolidated into one case containing both plaintiffs alleging crop damage and plaintiffs accusing Monsanto/Bayer of violating federal antitrust laws. A lawsuit accusing the Environmental Protection Agency of violating the law by approving dicamba-based pesticides for in-crop use has also been filed, as has a lawsuit by Monsanto/Bayer against the Arkansas State Plant Board for passing regulations effectively preventing the use of dicamba-based pesticides within the State of Arkansas.

This webinar will provide an overview of each of these lawsuits, a look at the claims being made by the plaintiffs, and what the outcome of each suit could mean for dicamba use in the United States.


Time and Date:

Wednesday, April 15th, 2020

12:00 – 1:00 (EDT)


This webinar is offered free of charge and is limited to the first 100 registrants. It is recommended that you test your computer for software compatibility prior to the webinar by clicking here.

This webinar was recorded April 15, 2020. To view a recording of this webinar, click here.


Brigit Rollins, Staff Attorney, National Agricultural Law Center

Brigit began her life in Sonoma County, in the heart of California’s wine country. Growing up, she was surrounded by small farms, dairies, and wineries, which ultimately led to a passion for agriculture and the environment. She attended Sonoma State University where she earned a Bachelor of Arts in environmental studies, and a minor in studio arts. While at Sonoma State, Brigit studied different types of agricultural methods and how those methods could be used to promote environmental sustainability. After graduating from Sonoma State in 2015, she started as a law student at Lewis & Clark Law School in Portland, Oregon. While at Lewis & Clark, she worked as a student clerk for the Western Resources Legal Center, where she worked on cases assisting small ranches, farms, and municipalities. During her time at Lewis & Clark, she also interned with the California Farm Bureau Federation, and worked as a law clerk for the Sacramento-based environmental law firm Somach Simmons & Dunn. While at the California Farm Bureau, Brigit focused on Environmental Species Act issues and water law issues, as well as issues specific to California. While at Somach Simmons & Dunn, Brigit expanded her work on water law and participated in work involving federal Indian law. On campus, Brigit was on the board of Lewis & Clark’s Food & Ag Law Society and served as a student member of the ABA Public Lands Committee.

Brigit began her work at the Center as a research fellow during her second year of law school. As a research fellow, Brigit worked on a wide variety of agricultural law topics ranging from liability issues to the new frontier of lab-grown meat. In 2019, Brigit graduated from Lewis & Clark and joined the Center full-time. At the Center, her primary area of research and scholarship is environmental law as it intersects with agriculture. She maintains an interest in promoting sustainability and environmental health through agriculture and resource use.

Research & Materials:

PowerPoint Presentation

The Deal with Dicamba: Part One, Overview (1/22/2020)

The Deal with Dicamba: Part Two, Lanham Act claims (1/29/2020)

The Deal with Dicamba: Part Three, State law failure to warn claims (2/12/2020)

The Deal with Dicamba: Part Four, Civil conspiracy claims (2/26/2020)

The Deal with Dicamba: Part Five, Trespass and nuisance claims (3/11/2020)

The Deal with Dicamba: Part Six, Sherman Act claims (3/25/2020)

The Deal with Dicamba: Part Seven, ESA and FIFRA claims (4/8/2020)

The Deal with Dicamba: Part Eight, Arkansas state court cases (4/15/2020)

The Deal with Dicamba: Ninth Circuit Vacates EPA Registration (6/5/2020)

The Deal with Dicamba: EPA Issues Cancel Order for Dicamba Herbicides (6/10/2020)

The Deal with Dicamba: Plaintiffs Challenge EPA Cancellation Order (6/18/2020)