Goodbye to Dicamba – For Now

by Ryan Nebeker


After a surprise ruling from the Ninth Circuit Court of Appeals last week, the EPA announced it was revoking registrations for several formulations of the herbicide dicamba, effectively banning its sale and use on US farms. Dicamba has been used for decades, but only recently became the center of controversy after it caused damage on millions of acres of crops. At the center of the controversy are documents appearing to show willful negligence on the part of Bayer and BASF, which manufacture the herbicides. While environmental groups and farmers have applauded the recent decision, will the court’s ruling hold?

What is Dicamba?

Dicamba has been in use since 1962, but its application was limited until recently. It works mostly against broad-leafed plants, making it a useful weed control measure for grass crops like corn. Early on, however, scientists noted that dicamba had a tendency to evaporate after spraying and drift onto other fields, where it stunted or killed other crops. Because of this, farmers were advised to limit their use of the chemical to areas where it couldn’t come into contact with vulnerable plants. Officials in states like Illinois advised against its use entirely due to the high risk of damage to other crops.

Like many other herbicides, dicamba fell out of favor after the introduction of “Roundup Ready” corn and soy in the 1990s, which is genetically engineered to resist Monsanto’s herbicide glyphosate. Because farmers could spray their fields with glyphosate without worrying about killing their crops, glyphosate became the first and last line of defense for many farmers. Overuse of glyphosate quickly caused the emergence of glyphosate resistant “superweeds,” so farmers turned back to older, more hazardous chemicals to keep up.

GMOs and the Resurgence of Dicamba

In looking for alternatives to glyphosate, Monsanto worked with the German chemical company BASF — the original developer of dicamba — to develop new genetically modified cotton and soy seeds that were resistant to dicamba. After several years, they released these seeds to the public.

The dicamba-resistant crops were designed to be treated much like glyphosate-resistant crops: dicamba could be sprayed “over the top” onto entire fields. Critically, Monsanto sold these seeds before the EPA approved this kind of spraying for the chemical. Over the top spraying of dicamba was a recipe for evaporation and drifting on a massive scale: illegally sprayed dicamba caused serious damage to neighboring fields in Arkansas and other states in 2016.

The EPA later approved three dicamba-based herbicides for over the top spraying, but skipped several steps of the approval process. Monsanto argued there was no need for independent testing, as they believed the new formulations were less volatile and that farmers urgently needed the chemicals approved to fight off superweeds.

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The Dicamba Drifting Crisis

Unsurprisingly, this decision had serious consequences: the approved herbicides turned out to be even more volatile than older dicamba mixes, which aggravated the drifting problem. In 2017, farmers planted about nearly 90 million acres of soybeans. Of those, 22 million acres of dicamba-resistant. Scientists estimated that 3.6 million acres of non-resistant soybeans alone were damaged by dicamba drift that year — nearly four percent of all soybeans in the country. Other crops, like peaches, grapes and tomatoes, were also damaged.

In response to the crisis, states designed regulations to try and limit dicamba drift, setting rules that restricted spraying in high temperatures and windy conditions. Farmers also tried to avoid damage by buying Monsanto’s resistant seeds themselves: nearly 60 percent of soybeans in the country were dicamba resistant in 2019. Even with these changes, 2019 was a record year for dicamba complaints in several states, with nearly all non-GMO soybeans in many counties showing damage. Foresters in parts of the Midwest also started to note damage to wild trees.

Dicamba drift also brought serious conflict to farming communities across the country. Neighbors who didn’t plant resistant seeds lost thousands in revenue, and formerly friendly neighbors fought over who was responsible for the damage. One Arkansas farmer even murdered a neighbor who confronted him when his dicamba damaged an orchard.

Legal Action

A number of farmers pursued lawsuits against Bayer (which purchased Monsanto in 2018) and BASF for pushing the use of dicamba. They claimed no responsibility for the dicamba damage, arguing it couldn’t be held liable for how farmers applied the chemical.

The owners of a peach orchard, Bader Farms, were the plaintiffs of the first suit to go to trial. In court, the prosecution unsealed internal documents showing Monsanto anticipated the drift and intended to use it as a fear-based sales strategy to get farmers to buy resistant seeds. Moreover, the documents encouraged Monsanto inspectors responding to complaints to seek out other reasons crops might have been damaged and to only investigate claims from customers in good financial standing. These practices delayed insurance payments and helped bog down legal cases.

Although Bayer and BASF lawyers argued in court that it was impossible to prove that the damage had come from dicamba and that the EPA had validated the safety of the products, the jury still found both companies guilty of negligence given the unsealed evidence. The jury awarded Bader farms $265 million in total damages, which Bayer later sought to appeal.

The End of Dicamba?

Meanwhile, other suits went after the chemical itself. A number of environmental groups filed against the EPA’s registration of the chemical, arguing the agency had failed to properly vet its use because it skipped independent review. In a major victory, judges of the Ninth Circuit revoked the approval of dicamba-based herbicides for over the top spraying, making it illegal to sell, distribute, and use the herbicides.

Because the ruling came in June — after most farmers had planted their dicamba-resistant soybeans — the Secretary of Agriculture and conventional agriculture lobbies criticized the ruling, asking for an allowance that farmers be able to use their existing stock. The EPA’s final cancellation order for the three dicamba-based herbicides allows farmers to use already-purchased chemicals through the end of July, but bans further sales. Plaintiffs in the case — the Center for Food Safety and the Center for Biological Diversity — filed a motion to stop all spraying now and hold the EPA in contempt of court, but it’s unclear whether the motion will be granted.

Bayer — already beleaguered from a slew of lawsuits around the safety of the main ingredient in its product Roundup — stands to lose nearly $100 million in sales this year from the decision, and says it plans to appeal. Although analysts disagree about whether or not an appeal is likely to be granted, it may not matter; the herbicides are up for renewal in 2021 if they can bring a different formulation or independent data that shows the chemicals are safe. To that end, Bayer has already signaled its intention to keep pushing forward on its registration for next year. This means the door on dicamba is hardly closed, and while settling the thousands of existing lawsuits in progress could cost Bayer and BASF billions, there’s still enough financial incentive for the companies to keep pushing to register dicamba in the future.

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