LAKE TAHOE BASIN, Calif. – A yearlong investigation by Mother Jones is casting new scrutiny on the use of glyphosate in California forests at the same time the U.S. Forest Service Lake Tahoe Basin Management Unit plans to use the controversial herbicide across thousands of acres in the Lake Tahoe Basin.
Glyphosate, commonly sold under the brand name Roundup, is widely used to kill shrubs and hardwood vegetation that compete with replanted conifers after fires and logging operations.
However, the herbicide has long been controversial. In 2015, the cancer research arm of the World Health Organization classified glyphosate as a “probable carcinogen,” and manufacturer Bayer has paid more than $12 billion in settlements tied to lawsuits alleging the herbicide caused cancer.
The Mother Jones investigation analyzed more than 5 million California pesticide records and found glyphosate use in the state’s forests reached approximately 266,000 pounds in 2023 — nearly five times the amount used two decades ago. The report identified forest spraying as the fastest-growing use of the herbicide in California.
The investigation also reported that a U.S. Forest Service safety assessment relied heavily on a study later retracted after allegations that it had been ghostwritten by employees of Monsanto, the agrochemical company best known for producing glyphosate-based herbicides before being acquired by Bayer in 2018.
For the Tahoe Basin, the findings are particularly relevant since the Forest Service approved the Caldor Fire Restoration Project in March 2026, a large-scale restoration initiative covering approximately 11,100 acres of National Forest System land on the south shore of Lake Tahoe that includes planned herbicide treatments, including glyphosate.
Within the project, there are approximately 4,900 acres where the probability of natural forest regeneration is less than 40 percent. Of those acres, reforestation actions — which include herbicide treatment — are proposed on between 2,400 and 3,600 acres.
The project area stretches from the southern shoulder of Echo Lake near Highway 50 eastward above Meyers and South Lake Tahoe, encompassing large sections of public forestland frequently used for hiking, camping, backcountry recreation and foraging.
Red pin marks the the Caldor Fire Restoration Project area.
Since the Angora Fire, the Tahoe Regional Planning Agency and the United States Forest Service have operated under a Fuels Reduction and Forest Health Memorandum of Understanding to streamline permitting processes for forest health and fuels reduction projects. While TRPA does not have jurisdiction over this project, they have reviewed and provided feedback on it.
According to TRPA, herbicide use is permitted under the agreement as long as it remains consistent with the TRPA Regional Plan and the agency’s Best Management Practices Handbook, particularly regarding limitations near stream environment zones.
“The safeguards and methods planned to be used will meet TRPA’s environmental standards.” said the organization. “The agency will continue to work with the LTBMU to ensure requirements are met, including signage and public notifications when the project is ready for implementation.”
During the National Environmental Policy Act stage for the Caldor project, TRPA requested that, because the project area experiences heavy recreational use, the Lake Tahoe Basin Management Unit notify the public where herbicide applications occur.
The action plan states herbicides would be applied using backpack sprayers or other low-volume methods to target the most competitive native plants. No aerial or aquatic application of herbicides would be used. Herbicide treatments would be used to assist with site preparation before tree planting and to manage competing vegetation after planting when manual treatments are ineffective or expected to be insufficient.
LTBMU said that despite the investigation, they have not discussed changes to the project. They added, “no herbicide application within the project area is expected in 2026/2027.”
Due to the continued deterioration of forest stands within the Caldor Fire burn area, the Lake Tahoe Basin Management Unit received an Emergency Action Determination for the project. The designation allowed the Forest Service to use emergency authorities to expedite implementation.
“Herbicides are used to treat invasive weeds in situations where manual removal is impractical or ineffective,” said a representative of LTBMU. “In some situations, shrub regrowth can shade-out seedlings, negatively affecting the survival rate.
“The Lake Tahoe Basin Management Unit has been thoughtful in its choice of areas for herbicide use, avoiding sensitive riparian habitats and times of year (June 1 to September 30) when pollinator species are most may have a higher chance of being impacted by application. The planned herbicide use associated with the Caldor Project is designed to be as minimal as possible and with the least amount of chemicals necessary.”
The overall project includes approximately 5,900 acres of wildland-urban interface land — the transitional zone where homes and infrastructure meet or intermingle with undeveloped wildland vegetation.
Preliminary survey work and site preparation activities are expected to begin spring 2026.
Officials stated the restoration project is intended to improve long-term forest resilience and help the landscape recover. But the scale of the proposed herbicide use near recreation-heavy public lands is drawing renewed attention as concerns about glyphosate continue nationwide.
Map of Caldor Fire’s Restoration project recreation opportunity spectrum in relation to forest restoration treatment activities.
A Change.org petition was started with the goal of stopping the use of glyphosate. As of Monday, May 11 at 7 a.m., there were 2,722 signatures.
Fact Sheet: President Donald J. Trump Ensures an Adequate Supply of Elemental Phosphorus and Glyphosate-Based Herbicides for National Security
The White House
February 18, 2026
BOLSTERING NATIONAL SECURITY BY PRESERVING CRITICAL SUPPLY CHAINS: Today, President Donald J. Trump signed an Executive Order mobilizing the Defense Production Act to protect domestic production of elemental phosphorus and glyphosate-based herbicides — two critical inputs essential to military readiness and America’s agricultural strength, respectively.
The Order finds that any interruption of supply of either of these critical materials could leave our defense industrial base and food supply vulnerable to hostile foreign actors.
The Order delegates the President’s authority under the Defense Production Act to the Secretary of Agriculture to require the performance of contracts or orders related to these materials to promote the national defense, and to determine the proper allocation of materials, services, and facilities necessary to ensure a continued and adequate supply of these products. It directs the Secretary of Agriculture to exercise that authority in consultation with the Secretary of War.
The Order directs the Secretary of Agriculture to issue orders and regulations as needed for implementation.
COUNTERING THREATS TO AMERICA’S DEFENSE AND FOOD SECURPresident Trump is acting to ensure domestic production of elemental phosphorus and glyphosate-based herbicides, the loss of which would cripple critical supply chains.
Elemental phosphorus is a key input in defense supply chains — crucial for smoke, illumination, and incendiary devices, semiconductors in radar, solar cells, sensors, and optoelectronics, and modern lithium-ion battery chemistries used in weapon system supply chains.
Elemental phosphorus is also a critical precursor element for the production of glyphosate-based herbicides, which are the most widely used crop-protection tools in U.S. agriculture — enabling efficient food and livestock feed production that protects food supply chains and ensures the availability of healthy, affordable food options within reach for American families.
With only one domestic producer of elemental phosphorus and glyphosate-based herbicides, and U.S. needs far exceeding current output, the threat of reduced or ceased production gravely endangers national security and defense, which includes food-supply security.
The Administration continues to support research and investment into next-generation crop protection technologies, but ensuring a stable supply of existing critical inputs remains essential to safeguarding food security and national defense.
ADVANCING AMERICA FIRST INDUSTRIAL STRENGTH: President Trump has consistently prioritized policies that secure domestic supply chains, protect national defense, and support American agriculture and families.
In March 2025, President Trump signed an Executive Order allowing the Defense Production Act to be used to expand domestic mineral production capacity.
In April 2025, President Trump signed an Executive Order to revitalize America’s maritime industry to strengthen the nation’s economic and national security.
In May 2025, President Trump leveraged the Defense Production Act to enhance domestic capability to manage spent nuclear fuel, as part of the Administration’s push to expedite and promote the production and operation of nuclear energy.
President Trump has repeatedly used Section 232 tariffs to protect against threats to our national security and to strengthen manufacturing sectors critical for our national and economic security.
President Trump has also secured billions of dollars in private-sector and foreign investments to expand domestic manufacturing capacity and strengthen America’s industrial base.
deliberate poisoning of soil air and water. Now who would do such an inhuman thing. An act of extreme calculated malice against an entire population. Note there is record of one criminal cabal that has a thousand + year history of poisoning water supplies and sabotage of infrastructure of neighboring tribes.
They make excuses for killing Us and disrupting the natural cycle sound so... Helpful.
Glyphosate is ghastly, but will profit those moneyed psychopaths in control on Our planet (by virtue of money) if They can sell Us this line and Their "product."
deliberate poisoning of soil air and water. Now who would do such an inhuman thing. An act of extreme calculated malice against an entire population. Note there is record of one criminal cabal that has a thousand + year history of poisoning water supplies and sabotage of infrastructure of neighboring tribes.
They make excuses for killing Us and disrupting the natural cycle sound so... Helpful.
Glyphosate is ghastly, but will profit those moneyed psychopaths in control on Our planet (by virtue of money) if They can sell Us this line and Their "product."
We might want to implement solutions:
A Breakdown of Why Abundancism is the Solution (article): https://amaterasusolar.substack.com/p/a-breakdown-of-why-abundancism-is