Ontario’s Toxic Legacy is a public record page documenting 70 years of herbicide spraying in Ontario’s public forests. It brings together historical records, scientific warnings, public opposition, Indigenous resolutions, municipal action, and policy developments that show why this practice should end.
Most Ontarians have no idea this is happening. About 94% of the province’s population lives in Southern Ontario, while the “Rain of Death” falls almost entirely on Northern forests and Treaty Territories despite decades of fierce opposition. That geographic divide has allowed governments and multinational forestry companies to ignore Northern voices for far too long. But the wall of silence is crumbling. The truth is getting out, and together we can force accountability on a broken system that puts corporate profit ahead of the health of our forests, waterways, wildlife and communities.
Decades of Warnings, Decades of Inaction
1950s–1970s → The Agent Orange Era
Ontario forests were sprayed with herbicides including 2,4-D and 2,4,5-T—the same two herbicide components used in Agent Orange. The danger was not just the herbicide itself, but its contamination with TCDD/dioxin, one of the most toxic synthetic compounds known to science. For decades, government and industry treated these chemicals as acceptable forestry tools. After years of public concern, protest, and reports of serious illness, Ontario restricted the use of 2,4,5-T in 1979 and made the final decision to ban its use and sale in 1980. Decades later, Ontario’s own Independent Fact-Finding Panel on Herbicide 2,4,5-T confirmed that some provincial workers, loaders, applicators, and Junior Rangers had been exposed to levels that exceeded safe thresholds. That history matters today, because Ontario did not end chemical forestry – it switched poisons.
1980 → When 2,4,5-T became impossible to defend, the industry didn’t stop, modernize, or transition to manual brush-clearing. Instead, they reached right back into the shed for the next chemical herbicide they had in line: Glyphosate. It wasn’t adopted because it was safe, it was adopted because the industry needed an immediate, cheap replacement to kill everything that would compete with their conifer plantations. For the next 40+ years, the public was handed the exact same corporate script: “Trust the regulatory approvals.”
1982 → Section 35 of the Constitution Act, recognized and affirmed existing Aboriginal and treaty rights, strengthening the Crown’s legal obligations when decisions may affect those rights. But spraying went on against their will.
1980s → Indigenous Nations begin passing formal resolutions opposing herbicide spraying citing harm to land, water, medicines, wildlife, treaty rights, and future generations.
“These Resolutions were passed in 1989 and 2004, respectively. Clearly, our concerns have not been met in these many years. ”
— Chief Keith Corston, Chapleau Cree First Nation
1989 → Warning ignored: A Canadian forestry study by Roy et al., conducted under boreal forest conditions at Matheson, Ontario, reported glyphosate uptake and persistence in wild blueberry and red raspberry fruit. Health Canada says it considered relevant published scientific reports during glyphosate’s re-evaluation, but its public materials do not clearly show whether or how the 1989 Roy et al. forestry soil study was weighed.
1999 → Federal warning ignored
Senate Subcommittee on the Boreal Forest After a two-year federal Senate study into the future of Canada’s boreal forest, the committee issued a blunt recommendation: “All herbicide and chemical pesticide use in the boreal forest should be phased out as soon as possible.” The report also devoted an entire chapter to “Aboriginal Realities,” examining Aboriginal rights, traditional land use and jurisdictional issues – recognizing that protecting the boreal forest must include respecting the people whose lives, cultures and rights are tied to it.
2000 → the Williams, Kroes & Munro (2000) Roundup/glyphosate safety review helped provide cover used to defend and continue forest herbicide spraying for another 25 years, until it was retracted Dec 2025.
2001 → Quebec ends Herbicide Spraying in Forestry and Industry adapts
Driven by intense public pressure, Québec becomes the only province to end chemical forest spraying due to environmental and public health concerns. They stopped issuing spraying licenses.
2007 → Political opposition placed on record at Queen’s Park
MPP Gilles Bisson presents petitions opposing forest herbicide spraying.
April 22, 2009 → Public Pressure wins protections, but FORESTRY IS EXEMPTED. After years of pressure from parents, doctors, nurses, health organizations, environmental groups and municipalities, Ontario restricted cosmetic pesticide use, including products containing glyphosate and 2,4-D, on lawns, parks and schoolyards. Yet decades of opposition and formal Indigenous resolutions against forest spraying were ignored. Ontario protected people from pesticides in public spaces. Why were people in public and Treaty forests denied the same protection?
2010s → Sierra Club Warns Against Plantation-Based Carbon Claims, calling for full-cost carbon accounting and said carbon-storage policies should prioritize protecting and restoring natural ecosystems rather than relying on plantations, monocultures and non-native species.
2015 → Global health alarm issued
The World Health Organization’s International Agency for Research on Cancer classifies glyphosate as “probably carcinogenic to humans.”
2015 → Political Accord promised change
Ontario and First Nations leaders signed a Political Accord meant to guide cooperation on resource issues. Spraying still continues without consent and in the face of fierce opposition.
2015 → Petition & Protests begin in Thunder Bay
2016 → Public protest reaches Parliament Hill
Communities and allies bring the issue directly to Ottawa as provincial governments continue to ignore calls to stop spraying.
👉🏻 2017 – French-Severn Forest sprayed with Garlon XRT A public forestry notice showed planned spraying in the French-Severn Forest with Garlon XRT, a triclopyr-based herbicide. That is why this fight cannot focus on glyphosate alone. When one chemical becomes harder to defend, industry cannot simply switch herbicides and continue Chemical Forestry under another name, as it did when glyphosate replaced earlier chemicals in the 1980s.
2017 → Health Canada’s Failure. Despite rising global concern, Health Canada re-approves glyphosate for 15 years. The re-evaluation cited the Williams, Kroes & Munro (2000) Roundup/glyphosate safety review in its reference list while concluding that glyphosate was unlikely to pose a human cancer risk and that registered uses would not pose unacceptable risks when label directions were followed. After that paper was formally retracted in 2025 over serious ethical concerns and undisclosed Monsanto involvement, Health Canada said it had not relied on that paper in reaching its decision. *** Safe Food Matters challenged the decision, beginning a legal fight that continues today.
2018 → The first major Roundup verdict – School groundskeeper Dewayne Johnson won a landmark $289 million (later reduced) jury verdict after jurors found Monsanto failed to warn about cancer risks. The case became a major turning point in the public story around glyphosate and Roundup.
2018–2019 → The Independent Alarm. While the government followed a Monsanto script, the independent Ramazzini Institute released a series of global pilot studies. They found reproductive harm, endocrine disruption, and altered gut bacteria at doses the government still claims are “safe.”
2019 – Glyphosate residues found in forest plants one year after forestry spraying
Woods et al. found glyphosate residues in forest plants one year after forestry application, including residues in roots, shoots, and fruit in some species. This confirms what forest-dependent communities have warned for decades: these chemicals do not simply disappear from the spray block.
2020 → Bayer agreed to pay nearly $11 billion to settle about 100,000 Roundup cancer claims: The deal set aside $8.8–$9.6 billion for existing cases and $1.25 billion for a separate future-claims arrangement. Bayer did not admit liability, but the scale of the settlement marked a major turning point in the Roundup litigation.
2021 → Glyphosate remains in forest plant tissues for a decade or more.
Botten, N., Wood, L.J. & Werner, J.R. – A peer-reviewed study published in Forest Ecology and Management examined glyphosate persistence in forest plants in northern British Columbia. Researchers found glyphosate residues persisted for up to 12 years in some plant tissues, with roots generally retaining residues longer than shoots. The study also found that colder northern conditions were associated with higher residues persisting for longer periods. Researchers noted that raspberry and blueberry fruit contained low quantities of glyphosate one year after treatment.
2021 → The “Consent” Law. Canada passed the federal UNDRIP Act, committing the government to work toward aligning federal laws with the declaration, including its standards concerning free, prior and informed consent.
2022-Present → billboards and event outreach (Sportsman Shows) to raise awareness due to the fact that most Ontarians have never heard of Forest Herbicide Spraying.
2023 December → An Ontario court certified a Canadian Roundup class action for people with non-Hodgkin’s lymphoma after significant exposure.
2024 → Earth Day mobilization demands Ontario STOP THE SPRAY
Stop The Spray Ontario, Indigenous Elders, Sierra Club, Safe Food Matters, and partners representing over 310,000 people publicly call on the province to end forest herbicide spraying.
2022–2025 → Safe Food Matters and allies challenge Health Canada, and win
Safe Food Matters, Friends of the Earth Canada, the David Suzuki Foundation and Environmental Defence Canada challenged Health Canada’s 2022 renewal of the glyphosate-based herbicide Mad Dog Plus. In 2025, the Federal Court found the renewal decision unreasonable and set it aside, ruling that the regulator had failed to transparently address newer scientific evidence on glyphosate risks. Still, glyphosate spraying continued.
May 1, 2025, all Registered Professional Foresters (RPFs) in Ontario are mandated to meet the Indigenous Peoples Lands & Resources (IPLR) Standard. This new professional competency requires RPFs to respect Indigenous jurisdiction and documented non-consent – making the authorization of the 2026 spray season a direct challenge to their professional standing.
2025 June → Independent Ramazzini Institute’s Global Glyphosate Study reported that prenatal-to-lifetime exposure to glyphosate and glyphosate-based herbicides caused multiple benign and malignant tumors in rats, including early-onset leukemia deaths, at dose levels corresponding to current EU regulatory thresholds.
2025 → First Nations and Métis opposition renewed
The Métis Nation of Ontario and the Chiefs of Ontario, representing 133 First Nations, again formally called for an end to forest herbicide spraying. These renewed resolutions show that decades-old concerns about lands, waters, foods, medicines, wildlife, health and Indigenous rights remain unresolved.
2025 → A Wave of Public Protests Take Place
2025 → Municipalities Take Action: Moonbeam, West Nipissing and Larder Lake helped open the door. Now 60 Municipalities + 1 Unorganized Community across Ontario are supporting existing resolutions or adopting their own to oppose forest herbicide spraying. 👉 View the municipalities Supporting the End of Forest Spraying
2025 December → The Scientific Shield Collapses. For 25 years, Williams, Kroes & Munro, 2000, helped support the public claim that glyphosate-based herbicides were “safe.” In December 2025, that review was formally retracted from the scientific record after serious ethical concerns, hidden Monsanto involvement, and undisclosed conflicts of interest came to light.
2026 February → Facing a mountain of new lawsuits, Bayer announced a massive $7.25 billion settlement to resolve claims that they “failed to warn” the public about the cancer risks of glyphosate, signaling that the company can no longer afford the legal cost of maintaining its “safety” narrative.
2026 → New forestry research adds yet another reason to move beyond herbicide-based forest management. A 2026 study in Forest Ecology and Management highlights trembling aspen as a natural fire barrier in Canada’s forests. That matters because forestry herbicide spraying is used to suppress broadleaf species in favor of conifer-dominated regeneration. In an era of climate change and smoke emergencies, this raises serious questions about continuing an old forestry model that removes mixed-forest resilience instead of protecting it.
2026 March → The Seattle Statement on Glyphosate and Public Health
International experts in epidemiology, toxicology, cancer, and risk assessment gathered at the 2026 Seattle Glyphosate Symposium to review newer independent science on glyphosate and glyphosate-based herbicides. Their Seattle Statement warned that glyphosate harms are not limited to cancer, but also include endocrine, neurological, reproductive, kidney, liver, metabolic, genetic, oxidative-stress, and hormonal effects. The scientists said the evidence of harm is now strong enough that no further regulatory delay is justified. They also warned that simply replacing glyphosate with other harmful chemical pesticides is not a real solution.
June 2026 → Ombudsman Refuses to Review 70 Years of Chemical Exposure
The Ontario Ombudsman refused to review fairness of 70 years of cumulative chemical exposure from Chemical Forestry, pointing back to Health Canada registration and provincial forestry policy. For communities, this was another lap around the Blame Circle: everyone points somewhere else while the spraying continues.
Ready to act? Hold them all accountable ~
- Chemical Forestry does not protect our forests, waterways, wildlife or communities.
- Transition to non-chemical forestry now.
