Why is High Park on fire? How Indigenous-led prescribed burns protect the land

High Park is on fire— but it's all part of the plan. 

The City of Toronto will be engaging in prescribed burns, an intentional preservation method, to protect the rare black oak savannah ecosystem within the park.

The city, which has been conducting prescribed burning for about two decades, had planned to hold High Park burns in late April or early May, but said in a statement they would instead begin Thursday, thanks to the balmy weather creating "optimal weather conditions" for the fire.

The method goes back to before colonization. Indigenous people who tended to the land used prescribed burns as a management tool for fire-dependent environments. Biinaakzigewok Anishnaabeg is the Ojibway name for the prescribed burn, according to the city. "It's always been a practice of my people to keep the land clean. In the old days, it was a way of rejuvenating new growth," said Henry Pitawanakwat, an Indigenous elder who identifies as being with the Three Fires Confederacy from Wiikwemkoong Unceded Territory. He is also one of the elders leading the opening ceremony for the burn Thursday.

As a result of the burning, the park will be closed to vehicles at 7 a.m. Thursday and will mostly reopen when the smoke has dissipated in the evening. Some areas will remain closed to pedestrians, the city says.

But what is the history of prescribed burns and how does the method work? Here's what you need to know about Thursday's fires. 

According to the city, a prescribed burn "is a deliberately set and carefully controlled fire that burns low to the ground and consumes dried leaves, small twigs and grass stems, but does not harm larger trees." 

Ray Vendrig, a manager of urban forestry with the city, told CBC Toronto the species within the black oak savannah ecosystem benefits from the burning because the heating of the ground helps with the germination of "desirable species" in the ecosystem and eliminates or slows the growth of invasive species. 

The ecosystem contains black oak savannah trees along with grass species and lupins, he said. 

In ideal weather, the smoke should not affect surrounding neighbourhoods, but those in the area are encouraged by the city to close windows and stay indoors during the burn if they are particularly sensitive to smoke. 

The black oak savannah's habitat is "extremely rare" and the city estimates that less than "three per cent of the original pre-settlement cover of prairie and oak savannah ecosystems remain in Ontario," it says on its web page dedicated to prescribed burn information.

High Park is the "most significant" area in the Toronto region containing this ecosystem, it says. 

Before the burning, an opening ceremony and smudge will be held, led by Indigenous elders.

Pitawanakwat told CBC Toronto that Indigenous knowledge around this type of ecological preservation has been well understood in many Indigenous communities and passed down. It's long overdue that Indigenous methods of land preservation are taken seriously, he said.