Two Toronto city councillors are warning that a towering, centuries-old red oak tree could be at risk without municipal protection.

The 25-metre red oak, believed to be the city’s oldest, is the subject of a motion in front of city council brought forward by Councillors Giorgio Mammoliti and Sarah Doucette.

The tree is on private property, and the property’s previous owners had agreed not to cut it down. Recently, the owners moved out of the home sheltered by the ancient tree, and put the property up for sale.

Without municipal rules protecting the tree, new property owners could buy the home and choose to chop it down.

The tree is believed to be between 250 and 350 years old, and may be the oldest red oak in the province, the councillors say.

"It's not often that you find a tree that's this old," Mammoliti told CTV Toronto on Wednesday.

It looms over a home on 76 Coral Gable Dr., in the Sheppard Avenue and Weston Road area of North York.

"If you were to view it from the street, the canopy of the tree almost covers the roof of the house," Forests Ontario CEO Rob Keen told CTVNews.ca.

Forests Ontario is working with city councillors to ensure municipal laws would protect the tree from being cut down.

The organization has already recognized the giant oak as one of the province’s "heritage trees" because of its age, but Keen says the "heritage tree" status is just part of a recognition program, and doesn’t actually provide any protection.

A motion presented to city council on Tuesday requests the city consider two options to protect the tree: acquiring the property or banning the property’s future owners from cutting it down.

"We're thinking about turning it into a parkette and allowing people to come and see the oldest red oak tree in the city," Mammoliti said. "I think it would make for a wonderful tourist attraction."

Keen said the red oak on Coral Gable Drive has shown genetic superiority, enduring centuries of harsh weather conditions. While smaller trees have died, the ancient red oak is still thriving in the North York backyard.

Keen pointed to climate change as a reason why genetically superior trees may be valued in the future.

Future seeds could be harvested and used to create "legacy trees," offspring that may have a better chance of survival based on the parent tree’s success.

Keen said he sees the ancient tree as an important part of the city’s heritage, so it should also be preserved for its historical value.

"We don’t have really old, old buildings like castles in Canada, but we do have these trees," Keen said.

"These trees are actually biological monuments to our history."