Stop Glyphosate From PoisoningLake Tahoe
The Forest Service used "Emergency Action Determination" to approve spraying glyphosate across 2,400–3,600 acres of the Caldor Fire scar without the standard public objection process! Our water, forests, and health are at stake and we must act NOW!
Take Action Now
The Forest Service approved glyphosate spraying across 2,400–3,600 acres of burned forest in Lake Tahoe.
In the wake of the devastating 2021 Caldor Fire, the USDA Forest Service's Lake Tahoe Basin Management Unit (LTBMU) released the Final Environmental Assessment and Decision Notice for the Caldor Fire Restoration Project on March 27, 2026. The overarching goal of the 11,700-acre project is to accelerate post-fire recovery and reduce hazardous fuels near communities like Heavenly, Sierra-at-Tahoe, and Meyers.
While the project includes necessary manual and mechanical thinning, it controversially authorizes "limited and targeted herbicide use" on 2,400 to 3,600 acres to aid site preparation before tree planting and manage competing vegetation. The chemical of choice is glyphosate, the active ingredient in Roundup.
While the USFS states no herbicides will be applied in 2026 or 2027, the authorization remains in place for the duration of the 10-to-15-year project. The USFS utilized an Emergency Action Determination for this project, waiving the standard pre-decisional objection process to expedite implementation.
The scale of this issue extends beyond the Caldor Fire footprint. Recent investigative reporting by Mother Jones and Reveal News uncovered that the USFS and private timber companies are systematically bombarding California's forests with record amounts of glyphosate. In 2023 alone, approximately 266,000 pounds of pure glyphosate were applied to state forests. Outraged citizens and environmental groups warn that total planned spraying across the Tahoe Basin and surrounding areas could eventually reach up to 75,000 acres if these practices are not stopped.
Critical Timeline
Emergency Action Determination
The USFS waived the standard pre-decisional objection process to expedite implementation.
10–15 Year Authorization
No herbicides in 2026–2027, but the authorization remains in place for the entire project duration.
Up to 75,000 Acres
Total planned spraying across the Tahoe Basin could reach 75,000 acres if not stopped.
Three reasons this cannot happen
Our Drinking Water
Glyphosate runoff from aerial spraying would directly threaten Lake Tahoe's crystal-clear water source.
Lake Tahoe is a pristine alpine watershed. Glyphosate runoff from aerial spraying would directly threaten this crystal-clear water source. When glyphosate is sprayed in forests, it does not stay on target weeds. It leaches into the soil and washes into the watershed, contaminating streams, rivers, and eventually the pristine waters of Lake Tahoe itself. A comprehensive USGS study detected glyphosate in 66 of 70 U.S. streams and rivers tested.
Fragile Ecosystem
Tahoe's high-elevation ecosystem is uniquely fragile. Glyphosate disrupts the vital microbiome.
Tahoe's high-elevation ecosystem is uniquely fragile and slow to recover. Glyphosate disrupts the vital microbiome and kills beneficial microorganisms that native plants and trees rely on to thrive. The EPA's own Biological Evaluation found that glyphosate is likely to adversely affect 93% of endangered species and modify 96% of critical habitats. By treating wild forests like commercial agricultural crops, we strip away natural groundcover, ferns, and shrubs that support wildlife, replacing vibrant ecosystems with sterile dirt.
Natural Regeneration
Fire scar areas are already regenerating naturally. Herbicide spraying suppresses this recovery.
Fire scar areas are already regenerating naturally through ecological succession. Native pioneer species are rebuilding the soil and creating habitat. Herbicide spraying suppresses this natural recovery and favors monoculture plantations over biodiversity. Studies consistently find that glyphosate application after wildfire suppresses natural succession and creates conditions for future invasive species establishment. Peer-reviewed studies demonstrate that even low concentrations of glyphosate-based herbicides in aquatic environments cause significant developmental impairment and high mortality rates in amphibians and fish.
The evidence is overwhelming
Independent scientists, federal courts, and international health agencies have all concluded the same thing: glyphosate is dangerous. Here are the facts.
Probably Carcinogenic
The WHO's International Agency for Research on Cancer classified glyphosate as "probably carcinogenic to humans" in 2015, based on strong evidence linking it to non-Hodgkin lymphoma.
Source: IARC Monograph Volume 112, 2015In Cancer Settlements
Bayer has paid over $12 billion to settle roughly 180,000 lawsuits from individuals who developed cancer after using Roundup, with a new $18 billion settlement announced in early 2026.
Source: The New York Times, February 2026Of Endangered Species
The EPA's own Biological Evaluation found that glyphosate is likely to adversely affect 93% of endangered species and modify 96% of critical habitats.
Source: EPA Biological Evaluation, 2020Ghostwritten Safety Study
The Williams Paper — a key 2000 study cited to prove glyphosate's safety — was officially retracted in December 2025 after being exposed as ghostwritten by Monsanto employees.
Source: Science.org, December 2025US Streams Contaminated
A comprehensive USGS study detected glyphosate in 66 of 70 U.S. streams and rivers tested, showing the chemical's pervasive presence in American waterways.
Source: U.S. Geological SurveyPotential Total Acres
Outraged citizens and environmental groups warn that total planned glyphosate spraying across the Tahoe Basin and surrounding areas could eventually reach up to 75,000 acres.
Source: Environmental advocates, 2026Glyphosate is probably carcinogenic to humans
“The evidence is clear: glyphosate poses unacceptable risks to human health and environmental integrity, particularly when applied aerially over watersheds that serve as drinking water sources and habitat for sensitive species. The retracted safety studies, growing litigation, and vacated EPA determinations tell us everything we need to know.”
Probably Carcinogenic
The WHO classifies glyphosate as "probably carcinogenic to humans" based on strong evidence linking it to non-Hodgkin lymphoma.
The International Agency for Research on Cancer (IARC), part of the World Health Organization, classified glyphosate as "probably carcinogenic to humans" (Group 2A) in 2015. This classification is based on strong evidence linking glyphosate exposure to non-Hodgkin lymphoma. California listed glyphosate under Proposition 65 as a chemical known to cause cancer, effective July 2017. Bayer has paid over $12 billion to settle roughly 180,000 lawsuits from individuals who developed cancer after using Roundup, with a new $18 billion settlement announced in early 2026.
Source: IARC Monograph Volume 112, 2015; OEHHA, July 2017The Retracted Williams Paper
A key 2000 safety study was exposed as ghostwritten by Monsanto employees and officially retracted in December 2025.
A key 2000 study often cited to prove glyphosate's safety — the Williams Paper — was officially retracted in December 2025 after it was exposed as being ghostwritten by Monsanto employees. The USFS has historically relied on industry-funded science to justify its use. This retraction undermines the entire foundation of glyphosate safety claims used by regulatory agencies. Furthermore, in 2022, the 9th Circuit Court of Appeals vacated the EPA's determination that glyphosate "is not likely to be carcinogenic to humans," calling the agency's analysis flawed.
Source: Science.org, December 2025; NRDC, June 2022Soil & Water Contamination
Glyphosate leaches into soil and water, disrupting the microbiome and contaminating the Lake Tahoe watershed.
When glyphosate is sprayed in forests, it leaches into the soil, disrupting the vital microbiome. It washes into the watershed, contaminating streams, rivers, and eventually the pristine waters of Lake Tahoe itself. A comprehensive USGS study detected glyphosate in 66 of 70 U.S. streams and rivers tested. Studies show even low concentrations cause significant biodiversity loss, leading to high mortality rates and deformities in amphibians and fish.
Source: Frontiers in Environmental Science; USGSDirect Community Exposure
Aerial spraying creates drift that exposes residents, hikers, and outdoor workers to inhalation and dermal contact.
Aerial spraying creates drift that extends well beyond target zones. Residents, hikers, outdoor workers, and children playing in affected areas would face inhalation and dermal exposure. The EPA's own assessment acknowledges risks to non-target organisms and nearby communities from aerial application methods near communities like Heavenly, Sierra-at-Tahoe, and Meyers.
Source: EPA Ecological Risk Assessment, 2020
The poison does not stay where it is sprayed
Glyphosate moves through soil, water, and air — creating a cascade of ecological damage that lasts long after the helicopters leave.
Aquatic Toxicity
Fish & Amphibian Mortality
Glyphosate formulations are toxic to fish, amphibians, and aquatic invertebrates at concentrations below agricultural application rates.
Glyphosate formulations are toxic to fish, amphibians, and aquatic invertebrates at concentrations well below agricultural application rates. Studies show mortality in Pacific chorus frogs and delayed development in rainbow trout. Even low concentrations in aquatic environments cause significant biodiversity loss.
Soil Destruction
Mycorrhizal Network Collapse
Glyphosate destroys beneficial arbuscular mycorrhizal fungi that form symbiotic relationships with 80% of plant species.
Glyphosate destroys beneficial arbuscular mycorrhizal fungi that form symbiotic relationships with 80% of plant species. Post-fire recovery depends on these fungal networks to restore soil structure, nutrient cycling, and carbon sequestration capacity. Without them, forests cannot heal.
Pollinator Poisoning
Bee & Butterfly Mortality
Glyphosate indirectly threatens pollinators by destroying flowering plants they depend on and directly through toxicity.
Glyphosate indirectly threatens pollinators by destroying flowering plants they depend on and directly through toxicity in formulated products. Sub-lethal effects include impaired navigation, reduced brood development, and colony collapse in native bee populations essential for alpine meadow ecosystems.
Water Contamination
Lake Clarity Degradation
Glyphosate and its metabolite AMPA persist in aquatic environments with a half-life up to 197 days in water.
Glyphosate and its metabolite AMPA persist in aquatic environments with a half-life up to 197 days in water. The Tahoe Regional Planning Agency has identified herbicide runoff as a threat to the lake's legendary clarity, which has already declined from 102 feet to 72 feet since 1968.
There are better ways to heal the forest
We do not have to choose between a recovering forest and a toxic one. There are proven, sustainable, and eco-friendly methods to manage post-fire vegetation and support reforestation.
“You don't need herbicides for fire recovery... The Forest Service is addicted to herbicide use and glyphosate, and we need to get them into rehab.”
Manual & Mechanical Thinning
Using hand crews and machinery (like masticators) to clear competing brush. This creates local jobs, avoids chemical contamination, and turns brush into protective mulch that retains soil moisture.
Prescribed Herbivory
Deploying herds of goats or sheep to naturally graze on invasive weeds and excess brush. Highly effective on steep, hard-to-reach terrain, naturally fertilizes the soil, and drastically reduces fire fuel loads without toxins.
Mulching & Wood Chipping
Grinding dead wood and brush on-site to create a thick layer of mulch. This naturally suppresses weed growth, prevents severe soil erosion into the watershed, and speeds up decomposition of nutrients back into the earth.
Biocontrol & Native Seeding
Introducing natural insect predators specific to invasive weeds, combined with aggressive, dense planting of competitive native seeds to naturally outcompete unwanted vegetation.
A healthy Sierra Nevada forest — the future we are fighting to protect
Four ways to fight back
Sign the Petition
Join over 5,200 others demanding an immediate halt to the glyphosate spraying plan. Every signature adds pressure on decision-makers.
Sign on Change.orgContact Representatives
Call and email your congressional representatives, state legislators, and local officials. Demand they intervene and halt the USFS plan. Urge federal representatives to support the No Immunity for Glyphosate Act (H.R.7601).
Join the Community
Stay informed and coordinate with other advocates. Join our groups to receive updates on hearings, rallies, and urgent actions.
Pressure the Agencies
Reach out to the Forest Service and environmental nonprofits sworn to protect the lake. Ask them to take a stronger public stance.
Join the Community
Stay in the fight
Get updates on hearings, rallies, and urgent actions. We will never share your information.
Resources & Toolkit
Everything you need to take action. Copy these posts, letters, and scripts directly — or adapt them with your own voice.
🚨 URGENT: The Forest Service is planning to spray toxic herbicides like Glyphosate (Roundup) across thousands of acres in the Lake Tahoe Basin to clear brush after the Caldor Fire. 🌲☠️ Glyphosate is a probable carcinogen that destroys soil health, kills wildlife, and will inevitably run off into our crystal-clear lake. We cannot let them poison the forest for the trees! There are safe, regenerative alternatives like manual clearing and goat grazing. 🗣️ It's time to stand up and protect the Jewel of the Sierra. 1️⃣ Sign the petition at Change.org to stop the spraying! (Link in bio) 2️⃣ Call the USFS Lake Tahoe Basin Management Unit at (530) 543-2600. 3️⃣ Share this post and tag @keeptahoeblue @trpa_tahoe to demand they fight this! #KeepTahoeBlue #StopGlyphosate #SaveLakeTahoe #ProtectOurForests #TahoeLife
The US Forest Service approved spraying thousands of acres in Lake Tahoe with herbicides like Glyphosate — a known toxin — for post-fire recovery. We don't need chemicals to heal our forests; we need regenerative solutions like manual thinning and grazing. Sign the petition to stop the spray! 🛑🌲💧 https://www.change.org/p/stop-glyphosate-spraying-in-the-tahoe-basin #SaveTahoe #StopRoundup #KeepTahoeBlue
Lake Tahoe is our sanctuary. It's where we breathe the crisp mountain air and marvel at the deepest blue waters. But right now, a plan is moving forward to spray thousands of acres of our surrounding forests with herbicides like Glyphosate (the chemical in Roundup) as part of a fire restoration project. This chemical is linked to cancer, destroys the soil microbiome, and will wash into our lake. We have to be the voice for the wildlife, the trees, and the water. We are organizing a peaceful but aggressive movement to demand the Forest Service use safe, non-toxic alternatives. Please, take 60 seconds to sign the Change.org petition, join our community group, and call your local representatives. Together, we can protect the heart and soul of the Sierra. 💙🌲 Petition: https://www.change.org/p/stop-glyphosate-spraying-in-the-tahoe-basin WhatsApp Group: [link coming soon]
As professionals and community members in the Tahoe region, we have a responsibility to protect our watershed. The Forest Service's proposal to spray glyphosate across thousands of acres of the Caldor Fire scar contradicts both environmental science and public health best practices. I am urging all stakeholders to review the Environmental Assessment and submit public comment. The business community, environmental scientists, and health professionals must speak with one voice. Learn more and sign the petition: https://www.change.org/p/stop-glyphosate-spraying-in-the-tahoe-basin
References
Partner Organizations
Sierra Club Lake Tahoe Group
tahoe@sierraclub.org
(530) 582-6782
League to Save Lake Tahoe
info@keeptahoeblue.org
(530) 541-5388
Tahoe Environmental Research Center
terc@ucdavis.edu
(530) 754-7333
Californians for Pesticide Reform
info@pesticidereform.org
(510) 788-8975