American farmers — and by extension consumers — are grappling with a problem a quarter century in the making. In the 1990s, St. Louis chemical company Monsanto developed Roundup Ready crops genetically engineered to tolerate heavy spraying of the company’s blockbuster herbicide Roundup. Today, this crop system defines American agriculture: over 89 percent of all corn, cotton and soybeans grown in the United States are genetically engineered to tolerate glyphosate — the active ingredient in Roundup.
Given the widespread use of glyphosate on Roundup Ready crops, environmentalists and health experts became concerned in 2015 when the World Health Organization’s International Agency on Cancer Research issued a report saying glyphosate was “probably carcinogenic to humans.” Because trace amounts of glyphosate can be found in food coming from crops sprayed with Roundup, some organizations urged consumers to turn to organic produce to avoid potential health risks. After all, organic foods by definition cannot be treated with synthetic pesticides like glyphosate.
But some organic growers that serve chemical-conscious consumers are currently under threat due to another herbicide called dicamba that Monsanto began selling in large volumes just a few years ago. Dicamba may be less well known than Roundup, but it is nevertheless dangerous in ways that have imperiled fruit and vegetable growers and organic farmers who seek to grow crops outside the genetic engineering (GE) seed system Monsanto created. It is therefore a hazard to the consumers who feed on the crops these food producers harvest.
The roots of our contemporary dicamba dilemma date back to the mid-1970s when Monsanto first brought Roundup to market. At that time, farmers were drawn to this new herbicide because it was particularly effective at killing a broad spectrum of weeds. In the 1980s, Monsanto researchers began investigating whether they could insert a gene from a bacterium into plants that would allow them to survive exposure to Roundup. Investing hundreds of millions of dollars in the project, the firm was ultimately successful in 1996 when it launched the first Roundup Ready crops, beginning with soybeans and canola and a few years later corn.
Now farmers could spray Roundup on their fields throughout the growing season without harming their harvest. It was a remarkable system, and it led to an explosion in Roundup sales.
Yet, while these crops seemed like a major advancement in agricultural production, there was a problem. Monsanto had told farmers that they could use glyphosate exclusively to kill their weeds. Roundup was the “only weed control you need,” the company exclaimed in a 1998 advertisement. But beginning in the late 1990s, agricultural scientists began identifying weed species that had developed resistance to Roundup due to its heavy use. In just a few short years, these weed adaptations threatened Monsanto’s entire GE seed system. By the 2010s, Roundup-resistant weeds had become so pervasive that farmers had few options but to turn to old chemicals like dicamba (first commercialized in the 1960s) to try to keep their fields clean.
Monsanto tried to solve the Roundup-resistant weed problem in 2015 and 2016 by introducing genetically engineered Xtend seeds designed to tolerate dicamba and Roundup. Farmers could now douse their crops with both herbicides throughout the growing season. Dicamba would kill the Roundup-resistant weeds, and glyphosate would kill everything else except the Xtend crops. It seemed like a simple fix.
But this fix, too, had a serious downside. When sprayed in the hot days of the growing season, dicamba had a tendency to vaporize, spreading onto adjacent farms that might not have dicamba-tolerant crops, damaging them.
This led to heated brawls in the heart of America’s farm country. By 2017, the EPA reported that there were over 2,658 ongoing investigations responding to complaints from farmers charging that dicamba sprayed by neighbors had drifted onto their property and harmed their plants. That year Monsanto introduced a new formulation of dicamba, XtendiMax, which it claimed dramatically reduced dicamba drift problems. The EPA also demanded that farmers add dicamba-free buffers on the edges of their fields and restricted when growers could spray dicamba on their crops to try to cut down on drift.
But farmer complaints regarding dicamba persisted, especially among fruit farmers and other growers who chose not to purchase Monsanto’s new Xtend seeds and therefore had no protection from dicamba drift.
In June 2020, the U.S. Court of Appeals for the 9th Circuit announced an injunction against the further use of dicamba on Xtend crops, saying it had “caused substantial and undisputed damage” across the United States, leading farmers into bitter disputes with one another. The crop system was threatening “to tear the social fabric of farming communities asunder,” the court declared, with farmers who wanted to avoid dicamba finding no way to escape the pesticide now drifting onto their property.
Even more troubling, Monsanto had apparently seen this coming. In Bader Farms v. Monsanto, a peach farmer charged that his orchard was damaged by dicamba that drifted from neighboring farms. During the 2020 trial, plaintiffs’ attorneys revealed Monsanto documents that showed the company believed the drift problem could actually help them sell their dicamba-tolerant seeds. They referred internally to farmers hit by dicamba drift as “driftees” and noted that “most driftee people” could be “turned into new users” of the company’s Xtend crops. “Push ‘protection from your neighbor,’” one 2013 slide read in a Monsanto meeting in which salespeople strategized about how to sell Xtend products.
In 2018, German life-sciences firm Bayer purchased Monsanto, inheriting the Xtend brand. The company has said that there is nothing wrong with its Xtend system. “Know that Bayer stands fully behind XtendiMax herbicide. We are proud of our role in bringing innovations like XtendiMax forward to help growers safely, successfully, and sustainably protect their crops from weeds,” the company told its clients in an email. Left unsaid was the fact that the weed resistance trouble XtendiMax aimed to solve was one that Monsanto had helped create by promoting the exclusive use of Roundup for so many years, which led to Roundup-tolerant weeds.
Some hope that regulators might soon step in, especially given the new leadership in President Biden’s EPA. In March 2021, an acting assistant administrator for the EPA issued a remarkable statement admitting that “political interference” had “compromised the integrity” of the environmental agency’s approval of the dicamba crop system during the Trump years. But as of this writing, the EPA had not stopped Bayer’s Xtend system — despite the 9th Circuit decision. The agency did adjust buffer zone requirements and further restricted how late this herbicide could be sprayed into the summer when it re-registered dicamba products for use in October 2020, but time will only tell whether this will stop drift from harming non-Xtend farmers this summer.
This story has deep implications for all Americans. Overall herbicide use has exploded over the past few years, thanks to Roundup-resistant weeds. Consumers seeking to avoid pesticide residues in their food may now face the risk of a wider variety of chemicals ending up in the goods they buy at the grocery store. More importantly, farms that want to operate outside Bayer’s GE-seed system — like organic ones — are going to have a hard time doing so as long as dicamba is allowed to drift off-target and damage fields without Xtend technology.
The Center for Biological Diversity, along with other NGOs, recently filed suit against the EPA, claiming the re-registration of dicamba in 2020 was illegal. Whether more consumers will add their voices to this protest is yet to be seen. But we have entered a new era in American agriculture, one in which dicamba drifting in the air has made it much more difficult for many food producers to farm. And this is problematic, because as Bayer spreads its Xtend seeds, the firm’s clients will use larger volumes of dicamba on their farms, which will undoubtedly create dicamba-resistant weeds that growers will have to beat back with a new arsenal of chemicals and GE seeds. Bayer’s new crop system, in other words, does not solve the weed problems seeded by Monsanto’s Roundup Ready system 25 years ago. It perpetuates them.