[URBAN NOTE] "Why Toronto’s Urban Forest is a Critical Infrastructure Asset"

[rfmcdonald]

In a sponsored post, Torontoist's Catherine McIntyre looks at the importance of Toronto's urban forest as a source of financial and other benefits.

When a resident from Kleinburg, a heritage district in York Region, proposed a plan to build an underground garage on his property, the City signed off with little dispute. The car park, complete with a hydraulic lift, would be close to the property line, but would offer just enough clearance from the neighbour’s mature trees to avoid causing any damage. Soon after the resident started excavating, however, the City was inundated with calls from a frantic neighbour. Major roots that stretched from their property into the excavation area were severed, cutting off a significant means of water and nutrient uptake, and the neighbour feared, correctly, that their trees would die.

It turns out the resident building the garage had mislead the City by submitting plans for the above-ground area of the project—a fraction of what was being excavated below the surface.

But according to Philip Van Wassenaer, a seasoned arborist and tree consultant for municipalities, knowing the construction would have damaged the roots wouldn’t have mattered anyway. “What’s below ground—40 to 50 per cent of the tree’s biomass—is the most important part,” says Van Wassenaer, “But if my tree is growing a metre away from the property line and you get permission to excavate to that point, then you’re going to be doing significant damage to a portion of the roots in my tree, and I have no recourse.”


Indeed, while municipalities have the mandate to protect the trunks, branches, and leaves of mature trees, the vital root systems remain largely ignored by policy, leaving them vulnerable to development.

It’s just one of the many limitations in the efforts to protect the GTA’s urban forest—a critical asset for healthy cities, and one that is increasingly under threat, from climate change, disease, and the built environment.