Smoke-filled skies and air quality warnings are becoming a feature of Ontario summers, but for most of the population, the source has felt far away.
As southern Ontarians stayed indoors or avoided strenuous activity under air quality warnings this summer, fires closer to home ignited. In July and August, the province experienced a number of wildfires in places including the Kawarthas, a couple hours northeast of Toronto, and near the town of Huntsville, in the cottage country region of Muskoka.
Farther north, First Nations communities like the Pikangikum First Nation and North Spirit Lake First Nation were evacuated due to wildfires and smoke — with more than 2,000 people sent to southern cities like Mississauga and Toronto for refuge, as well as the northern city of Thunder Bay. Various smaller southern cities also played host to wildfire evacuees from First Nations across the North.
Canada as a whole is experiencing its second-worst wildfire season on record. So far, more than 78,000 square kilometres have burned this year — that’s more land than the entire province of New Brunswick and more than double the 10-year average for this time of year. This massive uptick in Canadian fires can be attributed mostly to those raging across the Prairie provinces, like Manitoba, where about 20,000 square kilometres have burned.
How do wildfires in southern Ontario stack up to the massive fires farther north, and what can be done? Here’s what you need to know.
Are we seeing more fires in southern Ontario?
As of Sept. 2, there have been 521 wildfires inside Ontario’s fire region — the area north of Haliburton that’s within the jurisdiction of the provincial government. For comparison, there were 354 wildfires in that region in 2024, but the average number of fires over the past decade is 660, according to the province.
The province doesn’t count fires outside of the fire region, as they fall under local and regional governments, David Martell, professor emeritus at the Institute of Forestry and Conservation at the University of Toronto, tells The Narwhal. So, it’s difficult to know exactly how many fires are happening farther south.
But we are certainly hearing more about fires in southern Ontario. The fact that wildfires in these areas are rare, and happening close to big communities, is driving headlines, Chelene Hanes, a wildland fire research scientist with the Canadian Forest Service, says.
“They don’t happen very often, but they’re not unheard of,” she says. “Any fire of any size is going to have more media attention because there’s more people here, which ramps up the scale of concern — as it should.”
Is a fire in southern Ontario equal to a fire in other parts of Canada?
Compared to the north and other parts of Canada, fires in southern Ontario are different for two main reasons: the forest type and the many, many people here.
Southern Ontario is the most densely populated area in Canada, and there’s a lot of what those in the wildfire world call “interface,” meaning the places where forests and human developments meet, Hanes says. More interface means more wildfire suppression and prevention efforts year-round and little fires are generally put out very quickly, which can limit out-of-control spread.
The forests of southern Ontario are also home to more deciduous trees, which are a less effective wildfire fuel than the conifers of the boreal forest that cover much of the rest of the country.
Conifers that make up the boreal forest, like spruce and jack pine, are highly flammable and have low-lying branches that can allow a fire to climb quickly from the ground to the crown of the tree. The boreal forest is also dense, meaning once a fire climbs to the crown, it can easily jump from one to another, spreading quickly.
Firefighters respond to a wildfire near Parry Sound, Ont., in 2018. Climate change is making wildfires more likely in southern Ontario, as hot and dry conditions become more frequent and forest health deteriorates. Photo: Nathan Denette / The Canadian Press
“When we hear about big fires in the North in the news, those are typically conifer forests,” explains Mike Wotton, a research scientist with the Canadian Forest Service, based at the University of Toronto.
But deciduous trees, and their leaves in particular, hold more water and burn slower. If a fire does spark in these forests, it’s less likely to find low-lying branches and other fuel to climb in order to reach the crown, where it can start to spread.
If you think of a deciduous or hardwood tree, like a maple or oak, it has a bushy top. Pressed together with other deciduous trees, that closed canopy leaves little room for sunlight and its heat to get through, Wotton says, creating less of a fire risk on the ground.
Why was there such a high fire risk in southern Ontario this summer, then?
In short, climate change.
Climate change is altering Canada’s weather patterns. As greenhouse gas emissions, like those emitted by burning fossil fuels, trap the sun’s heat, temperatures around the world rise and extreme weather events like droughts, floods and wildfires become more common. Canada is actually warming at twice the global average, according to a climate report released by the federal government in 2019.
This summer, much of southern Ontario has experienced hot and dry weather, with many areas experiencing days-long Environment Canada heat advisories. Coupled with strong winds, these are “perfect conditions for fire to occur, especially when those fields are really dry on the surface,” Hanes says. “Any spark, whether from an unattended campfire or a cigarette, when those surface fields are extremely dry, it doesn’t take much to get an ignition going. Add wind and fire can expand quite quickly.”
Climate change is also altering the health of Ontario’s forests. According to Trevor Jones, a research scientist at Natural Resources Canada’s Great Lakes Forestry Centre, mortality rates of forests are changing. For trees that are already in a less-than-ideal zone, climate change is altering their environment and making it even harder for them to thrive.
Sugar maples, for example, are used to having more moisture. “If you start to turn the screws on them with these drier, hotter conditions, they start to experience greater mortality, which leads to standing dead trees on the landscape,” Jones says.
Those dead trees result in more branches dropping and more sunlight hitting the forest floor, which leads to a vicious cycle: though important to forest health, until they decompose, dead branches and leaves on the ground provide more potential fuel for fires, and the added light helps smaller trees and vegetation grow there as well. That dense underbush can also dry out in the additional sun, particularly if it’s coniferous, providing more fuel for wildfires.
Jones says the changing climate is also shifting the types of species in this part of the country and, therefore, how the forest interacts with wildfire.
“It takes a long time for forests to change, so they’re suffering for quite a while before change is evident,” Jones explains. It can take decades or even centuries for tree species that are more adapted to the new conditions to take over, he says. But there are some species shifts occurring, like in parts of Algonquin Park, just east of Huntsville, where they’re seeing more and more sugar maples die off. “We’ve been seeing it for a while and I think we’ll continue to see more of it,” Jones says.
What can I do if my property is at risk?
Across the board, experts recommend following the FireSmart Canada program for guarding against wildfires, and protecting properties in particular. Founded in 1993, the program teaches you how to keep your home safe by conducting an assessment, managing the vegetation around your house and using fire-resistant building materials. There is also an online training course that can help homeowners learn more about fire-smarting their home.
In an email to The Narwhal, a spokesperson for the Ontario Ministry of Natural Resources’ Aviation, Forest Fire and Emergency Services branch says making a small change around your property can have a big impact. “One example would be to reduce what is called ‘ladder fuel’ that may be around a home or cottage. Ladder fuel can be branches or shrubs that could carry a ground fire to the crown of larger trees,” the spokesperson writes. “Start by pruning branches to a height of two metres from the ground, especially on conifer trees. This is an important step to take to FireSmart your property.”
And, of course, adhering to fire bans and the law is critical, as is limiting the use of equipment like quads that could spark a fire in a high-risk area. If you do spot a wildfire in southern Ontario, call 911.
Are all fires bad?
No.
Fire is a natural part of a forest’s life and necessary for its regeneration. Some trees, like jack pine, need fire to open their cones and release their seeds. Across Canada, government agencies use controlled, prescribed burns to help regenerate forests and keep them healthy, including the Ontario government and Parks Canada. In Toronto’s High Park, the city holds regular prescribed burns to regenerate the park’s black oak savannah.
For many Indigenous communities, fire is an important part of their cultural practices and stewardship of the land.
Amy Cardinal Christianson, the senior fire advisor for the Indigenous Leadership Initiative and a Métis woman from Treaty 8 territory in Alberta, researches Indigenous fire stewardship, including cultural fire practices, Indigenous firefighting and better evacuation and recovery responses after fire.
There isn’t a pan-Indigenous approach to fires, Christianson says, but many Indigenous communities conduct burns to achieve cultural objectives. That might mean improving the health of medicinal plants, increasing berry patches, regenerating grasslands and more. Cultural burns “create healthy forests that have less dry and dead vegetation and monoculture-type forests that are more likely to burn in these high-severity fires.”
Unlike government prescribed burns, Indigenous cultural fires always have a community and cultural purpose and take place on a more grassroots level. While agencies might burn whole areas using helicopters, torches, gas and diesel, even a small bush-burning can be considered a cultural burn, Christianson says.
Across Canada, Indigenous communities represent just five per cent of the population, but made up 42 per cent of wildfire evacuations from 1980 to 2021. Despite that, “Indigenous people have been effectively removed from being able to make any sort of management decisions about fire,” Christianson says. “What we’re seeing is increasing risk to Indigenous communities and sadly, we’re the ones bearing the brunt of the impacts of these decisions.”
Along with climate change exacerbating fire risk, part of why Canada is experiencing so many “bad” fires is years of colonial forest management strategies and an idea of conservation that aims to preserve the environment rather than live in harmony with it, Christianson says. Despite some prescribed burns in some areas of Canada, settlers are still mostly “focused on fire exclusion and putting fires out.”
“The boreal forests and other forests in Canada are fire-dependent,” she adds. “No matter how much we try to control that or change that, that doesn’t change the relationship that that forest has with fire.”
