How prescribed burns can help ecosystems thrive

Hayley Reid-Ginis · CBC News

· Posted: May 21, 2025 4:00 AM EDT | Last Updated: 10 minutes ago

The leafy trees that operation implicit Toronto's High Park are 1 of the past remaining achromatic oak ecosystems successful Ontario.

They're rare, truthful each year, occurrence specialists cautiously acceptable fires adjacent their roots, successful a controlled perimeter  — burning disconnected the adust grass, leaves and twigs.

Smoke billows supra the trees, drifting done parts of the parkland earlier dissipating. The flames linger wherever they're set, turning the underbrush to ash.

The accepted and prescribed burns successful High Park person gone connected for 2 decades, named Biinaakzigewok Anishnaabeg by the Indigenous Land Stewardship Circle that collaborates with the City of Toronto connected the present-day rendition of what was a longstanding Indigenous practice.

While assemblage rules successful Canada agelong banned the accepted occurrence practices of Indigenous communities, that's been shifting, with much usage of prescribed burning not conscionable for wildfire extortion but ecosystem health.

Renny Grilz is simply a assets absorption serviceman for the Meewasin Valley Authority, a conservation enactment successful Saskatoon that uses prescribed fires successful and retired of metropolis limits.

"Part of conservation for, you know, the past 30 years was 'Set it aside, quality volition look aft itself,'" said Grilz. 

"We're realizing that no, we request to negociate these landscapes."

Fire arsenic a instrumentality successful municipality areas 

The thought of a prescribed pain is to usage a fast, debased occurrence on crushed level. 

Introducing occurrence to an ecosystem helps bladed the wood of fuel, which tin see things similar leafage litter, sticks, and dormant plants. In High Park, this gives fire-resistant taxon similar achromatic oak the abstraction to thrive by burning backmost invasive taxon and allowing much air, nutrients and sunlight to scope them.

In March of this year, the City of Edmonton conducted its archetypal prescribed pain wrong metropolis limits, to trim wildfire risk.

"This pain helped the metropolis efficaciously trim vegetation that could person fueled wildfire, and helped summation nationalist information by lowering wildfire hazard successful the area," Graeme McAlister, lawman occurrence chief, Community Safety and Risk with the City of Edmonton said successful an email to the CBC News.

But conducting a prescribed pain successful an municipality country comes with risks.

"You person precocious worth assets surrounding the country that you privation to burn, but besides fume absorption becomes precise critical," said Grilz.

Winnipeg has been conducting prescribed burns since the 1980s, for example, but Grilz says that different municipality areas similar Calgary, Regina and Moose Jaw, Sask., person expressed involvement successful prescribed fires, too. 

"As they [urban areas] beforehand their accomplishment sets oregon cognition basal wrong these municipality areas and their readying areas, they're starting to look astatine occurrence arsenic a absorption tool," Grilz told CBC. 

"It's truly exciting."

Helping autochthonal plants

In densely populated Southern Ontario, tallgrass habitats person a captious role, but they're successful danger. They supply habitats for ground-dwelling birds similar bobolinks and Eastern meadowlarks, some protected taxon successful Canada.

"Tallgrass communities person been drastically reduced, similar little than 1 per cent of what primitively was successful confederate Ontario remains arsenic autochthonal tallgrass. So we're trying to bring that assemblage back," said Adam Brylowski, manager of conservation and way astatine the Bruce Trail Conservancy, a non-profit enactment that manages onshore on the Niagara Escarpment UNESCO World Biosphere.

The Bruce Trail Conservancy takes connected ecological restoration projects, leaning heavy connected planting trees and wildflowers successful the past, according to Brylowski. 

In 2019, they recognized the value of tallgrass prairie restoration, too. After readying and preparing a site, the Bruce Trail Conservancy conducted their archetypal prescribed pain successful 2022.

The autochthonal grasses request occurrence for their seeds to germinate, but it tin termination disconnected invasive taxon similar Kentucky bluegrass and crested wheatgrass.

The Royal Botanical Gardens (RBG), spanning immoderate 800 hectares on the shores of Lake Ontario betwixt Burlington and Hamilton, besides uses prescribed burns. 

The RBG has conducted burns astatine antithetic sites since 1997, though they don't bash them each year.

This year, the extremity was to amended uncommon works habitat, according to a nationalist notice. This includes large bluestem and goldenrods, some autochthonal taxon successful tallgrass prairie ecosystems.