The herbicide glyphosate has been in the news a LOT in recent years. However, as we celebrate significant legal restrictions in California and Vermont on paraquat (another major herbicide) there is still no end in sight for glyphosate with its vast impacts on human health and the environment. Although far more glyphosate (brand name Roundup™) is sprayed on croplands, forest uses have become the herbicide’s fastest-growing market in California. In 2023, the last year for which use data are available, 266,000 pounds were applied to California forests. That’s nearly five times what it was two decades ago. The victims of herbicide application on forest include communities near impacted forests, forest workers who apply the pesticides, and Native Americans and others whose health and livelihoods depend on the use of forest resources.
Glyphosate history
Glyphosate was first sold to farmers in 1974. Since the late 1970s, the volume of glyphosate-based herbicides applied has increased approximately 100-fold. It is most heavily used on commodity crops such as corn, soy, and wheat. We’ve seen the biggest increases associated with development of glyphosate-resistant crops designed precisely to increase use of the herbicide. By 2016 genetically engineered herbicide-tolerant crops accounted for about 56% of global glyphosate use, far surpassing all other pesticides in intensity of use and geographic coverage.
In 2016 a group of scientists produced a consensus statement recognizing the World Health Organization’s International Agency for Research on Cancer conclusion that glyphosate is “probably carcinogenic to humans”. Their conclusions include that: (1) glyphosate-based herbicides (GBHs) are the most heavily applied herbicide in the world and usage continues to rise; (2) GBHs often contaminate drinking water sources, precipitation, and air, especially in agricultural regions; (3) GBHs persist in water and soil is longer than previously recognized; (4) glyphosate and its metabolites (the substances it breaks down into over time) are widely present in the global soybean supply; and (5) human exposures are rising—a point emphasized in a chilling 2017 report on glyphosate in our food. The scientist group identified many important remaining information gaps and regulatory needs.
In 2019 a California jury held Bayer/Monsanto responsible for a couple contracting non-Hodgkin’s lymphoma because of exposure to Roundup™ and awarded $2 billion over cancer claims. To date, more than 170,000 lawsuits linking Roundup™ to non-Hodkin’s lymphoma and several other cancers have payouts totaling nearly $11 billion in settlements. However, a May 2026 article from The New Lede revealed a rich payout to lawyers with little for plaintiffs. As the cases mount, so too do other efforts to protect the public from glyphosate exposure including a 2023 legal petition by PAN, the Center for Food Safety and others demanding a glyphosate ban.
Bayer and its government cronies push back
In 2000 presumably reputable researchers published a review article in the peer-reviewed journal Regulatory Toxicology and Pharmacology in which they falsely claimed that: “There is no potential for Roundup™ herbicide to pose a health risk to humans.” It was later discovered to have been ghost written by Monsanto and based entirely on research funded by Monsanto, as were several similar studies. The article was retracted in 2025, as reported in a story covered in The New Lede.
Then in February of 2026, as part of a long history of legal and regulatory favors to Monsanto/Bayer, the White House invoked the Defense Production Act—an executive order to guarantee supplies of glyphosate-based herbicides and elemental phosphorus—a key ingredient in the production of glyphosate. Then in June the U.S. Supreme Court ruled that federal pesticide law limits lawsuits against Bayer for not warning about cancer risks.
Also in 2026, the U.S. Forest Service pulled out the stops to support a massive increase in use of glyphosate, not in agriculture, but in U.S. forests—both those devastated by wildfires and clear cutting logging. Forest Service recovery plans are supposed to use workers to remove selected trees, cull undergrowth, and set prescribed fires, something like what Native Americans have done for millennia to keep forests healthy and reduce the risk of megafires. The agency also would plant new trees in burned areas where few had survived.
However, in a horrifically misguided plan here in California and elsewhere, the agency started earlier this year by spraying glyphosate on some 10,000 acres of public land in Lassen County to wipe out leafy plants and shrubs that might compete with replanted conifers. Mother Jones reporters discovered that forest spraying, unbeknownst to most of the public, is happening at record levels. They describe a scene where nearly five years after the Dixie Fire (that burned 963,309 acres in Butte, Plumas, Lassen, Shasta, and Tehama counties) the forests remain desolate with very little regrowth of the previously abundant cedars, pines, firs, and more. In fact, the Forest Service and logging companies claim they use glyphosate, “because it helps commercially attractive conifers like pine and Douglas fir rebound faster after fires and timber harvests. It does so by killing deciduous trees, native shrubs, flowering plants, and anything else that might compete for water, nutrients, and sunlight. In short, a key rationale for spraying a disputed chemical in natural settings boils down to executives and regulators treating forests, including our national forests, as tree farms.”
The Forest Service plans to follow the first round of spraying with another this fall. The agency justifies the plan using its 15 year-old risk assessment that repeatedly references the 2000 Monsanto ghost-written paper that was retracted in 2025. The irony of firms and government agencies spraying replanted burn zones is that they may be setting us up for more trouble down the road. Deciduous hardwoods such as oak, aspen, and birch can slow a fire’s progression, studies show, whereas resin-filled conifers are more flammable than other trees. A densely packed commercial conifer forest is, according to a growing scientific consensus, a megafire waiting to happen.
The victims of this forest apocalypse fight back
Herbicide spraying in forests kill broadleaf plants, berry bushes, and culturally significant flora used by Native peoples such as the Maidu who, for generations have relied on forest resources for food, basket weaving, and healing. As a consequence, the Maidu and other Indigenous Californians face severe cultural, health, and ecological threats from an increasing use of glyphosate and other herbicides in the state’s forest lands.
One piece of good news came in 2019, after a decade of advocacy and planning, the Maidu successfully won their proposal to regain ownership and stewardship of Humbug Valley, located in Plumas County. This marked the first time ancestral lands have been returned to a federally an unrecognized California tribe, a move encouraging others to pursue claims to lands with cultural and sacred sites. Together their determination to demonstrate the value of their traditional ecological knowledge has won them widespread support among local environmentalists and statewide fishing groups—even county and national forest officials. Under the recovery plan the Maidu will continue ancestral practices—all of which are threatened by herbicide applications—such as digging edible bulbs and roots to encourage more growth; pruning willows to improve their value for basket weaving; and using controlled burns to recycle nutrients and reduce fuel load.
Not only is this a story of perseverance and justice, it’s also personal to me. For the past 25 years my family has spent a precious week every summer on ancestral Maidu lands managed, in part, by the Forest Service in Plumas National Forest and in an area that includes what is now covered by Lake Almanor in the foothills of the Sierra Nevada at the headwaters of California’s Feather River. But now, when my grandson plays outside during these annual family trips, we’ll be worried if he’s being exposed to an herbicide that could have negative health consequences years down the road.
Stand up against continued use of toxic herbicides in our forests
If Quebec, one of the largest timber-producing regions in North America, can eliminate glyphosate and other herbicides in 90 percent of its forests we can too. Back in 1994, the province put in place a “forest protection strategy” designed to balance jobs and profits with healthy forests. Glyphosate, once widely used, was banned in 2001, and logging companies switched to manual and mechanical methods to stifle plant competition with minimal effects on yields, according to a 2010 government study. Now, instead of enriching a German chemical company, the money goes to pay local workers. Ignoring the Canadian case, Gov. Gavin Newsom signed an emergency executive order in 2025 allowing the state Department of Forestry and Fire Protection (Cal Fire) and other agencies to bypass normal safety procedures when spraying glyphosate.
In contrast, Native people here in California and beyond have for millennia managed forests in a safe way that has preserved their cultural traditions and protected an essential resource for us all. A recent UC Berkeley study found that forest biomass in the Klamath Mountains region used to be approximately half of what it is now, and that burns carried out by the Karuk and Yurok tribes played a significant role in maintaining forest integrity even during periods of climate variability. In one piece of good news, a 2022 California law, affirmed the right to cultural burns, reducing the layers of liability and permission needed to set “good fire” on the land.
Fortunately, in recent years the frequency and intensity of wildfires have raised serious questions about the wisdom, or lack there-of, of government forest management policies. In addition to growing concerns about the hazards of pesticides, the public is beginning to recognize Indigenous forest management practices as one of the keys to unraveling the deadly cycle of California wildfires. A key result of such practices that include managed harvest of multiple species and cultural burns is maintaining biodiversity, good forest structure and healthy ecological balance. Unfortunately, however, we still face bad policy proposals and there is an urgent need of organized public opposition
Act NOW to help prevent more bad policy
SB 1370 has passed the California legislature and is headed for the Governor’s desk. This bill would waive California environmental laws for large-scale projects up to 3,000 acres in the name of wildfire prevention. Environmental groups are sounding the alarm that SB 1370 would have disastrous effects for California communities and ecosystems. SB 1370 would make Governor Newsom’s temporary emergency proclamation for wildfire projects permanent. This would remove most statewide environmental regulations, and could expose Californians to dangerous pesticide spraying and toxic pollution without the normal state regulations. Projects encompassing more than 38,000 acres of herbicide spraying across the state have already been approved. It’s our responsibility to speak up and make sure public lands are stewarded well and managed safely, so that they can continue to be enjoyed by future generations.

