Trees with trunks growing across property lines are called “boundary trees” or “shared trees.”
Boundary trees can sometimes lead to disputes between neighbours—especially if one neighbour wishes to remove a tree for construction purposes, a development project or for other reasons. A recent Ontario legal ruling established stronger protections for boundary trees in urban areas, and sought to clarify some of the rights and responsibilities of co-ownership. The information on boundary trees contained in this site is based on this Ruling, (2013) copies of which are available on this site.
Becoming aware of these rights and responsibilities is a good step toward better stewardship of our trees, as well as avoidance of costly court fees.
In the province of Ontario, the applicable law is the Ontario Forestry Act and applies to trees growing in urban areas. Boundary trees are defined in the Forestry Act (Section 10.2) and are considered shared or co-owned property. The Forestry Act indicates that it is a prosecutable offense for one co-owner to injure or cut down a boundary tree without the other co-owner’s permission. Under the Act, failure to acquire the consent of a co-owner can lead to a fine of $20,000+ and/or 3 months in prison.
The 2013 Ruling established that the “trunk of a tree” includes everything from the root-collar to the tree’s first branch. If any portion of the tree’s trunk (whether at the base or above it) crosses the property line—it is considered a boundary tree. In many situations, the base of a tree may be on one side of the property line, but at another point, higher up on the trunk, it crosses the property line. It is important to be aware that there are many points on a tree’s trunk that can cross a property line. If any portion of the trunk crosses the property line, a tree can be legally considered a boundary tree and treated as co-owned property. (Photos of boundary trees are available here and can help you to discern your tree’s status as a boundary tree using the criteria established by the 2013 Ruling.)
Note: even if you or your neighbor has obtained a City-permit to cut down the tree, it does not give you/him/her automatic rights to do so. A City-permit does not automatically cancel out anyone’s property rights in a co-owned tree. (If you read the fine print on a City permit, usually there is a clause to this effect.)
A CAUTION to homeowners and developers about cutting down a boundary tree without a co-owner’s permission!
Since 2013, home-owners, developers and contractors in Ontario have found themselves in expensive court-cases for cutting down boundary trees without the co-owner’s permission. Fines have ranged from $6,250 to $37,000. Contractors have also faced civil suits for monetary damages. Read the Feb. 3 2018 Toronto Star article by property law expert, Bob Aaron: “Homeowners should always get neighbours’ permission before taking down boundary trees” here.
PROTECTING existing trees is just as important as planting trees:
Sometimes trees can become dangerous and unsafe, and clearly tree safety is something everyone should want and be entitled to. But if your shared, boundary tree is a healthy tree, co-owners should think carefully about preserving it. Why? The size of a tree and the amount of healthy leaf area equates directly to the benefits provided to your household and the community. For example: a tree with a 75 cm diameter intercepts 10 times more air pollution, can store up to 90 times more carbon and contributes up to 100 times more leaf canopy than a 15 cm tree.
Toronto’s “urban forest” consists of over 10.2 million trees, 60% of which are on private property—so private homeowners are the majority stakeholder group in tree conservation. While it’s important to plant new trees, conserving existing trees is also crucial to a healthy urban forest. (Read more on the benefits of trees for cities in Every Tree Counts.)
TREES ARE A PRECIOUS URBAN RESOURCE:
Trees growing on private lands are part of a larger ecosystem called the urban forest. All trees filter air, absorb carbon, provide shade against UV rays and provide habitat for urban wildlife. Trees are generous: they are life-giving not only for individual home-owners, but also for the larger neighborhood, including animals in “the hood.”