Tree Liability Risk: The Duty of Care Owed to Persons Who May Be Harmed by Trees

Question: What are the legal responsibilities for tree maintenance in Ontario?

Answer: In Ontario, property owners owe a duty of care to ensure trees on their premises are safely maintained to prevent injury or damage. As set out in the Occupier's Liability Act, R.S.O. 1990, c. O.2, failure to address known or constructively known hazards can result in liability. Proper and timely maintenance is essential, especially after events like severe storms that might compromise tree safety. To mitigate risks and legal responsibilities, proactive tree care is crucial. For personalized legal guidance on tree maintenance and liability, consult with us to protect your interests.

Liability Involving Tree Maintenance

Although trees are extensively found throughout our urban and rural landscape, the value and benefits of trees are often taken for granted. Additionally, the potential liability risks are often unappreciated or misperceived. Owners and contractors, among others, should carefully heed the potential liability risks arising from the ownership, care, or control, of trees.

The Law

Duty of Care

The basic principles of common law, particularly negligence and the legal test regarding duty of care as founded within the Donoghue v. Stevenson case (a general principles case rather than tree specific case), prescribe that property owners owe a duty to ensure that other persons and the property of others persons is reasonably safe. In Ontario, these duties are also codified the Occupier's Liability Act, R.S.O. 1990, c. O.2, whereas it is said:

Negligently Performed Maintenance

Owners of trees, or others responsible for trees (such as hired maintenance contractors), generally face liability only when it was known, or constructively known, that a tree failure risk was present and the owner (or others) failed to properly tend to the tree.  In this way it can be thought that the injury or damage was a result of delay in caring for the tree rather than the result of risks inherent in a tree.  Essentially, the negligent failure to maintain is a man-made risk rather than a natural tree risk. On the point of liability for failure to maintain trees, such was addressed within the case of Hallok v. Toronto Hydro Electric System Ltd., 2003 CanLII 8519, wherein it was said:

As such, it seems that knowledge, or constructive knowledge, of a dangerous condition is a requirement of liability for negligent maintenance of trees.  Note that "constructive knowledge" is knowledge which the law deems a person ought to have based on reasonableness.  If a reasonably diligent person would know of a dangerous condition this is "constructive knowledge" and proving actual knowledge becomes unnecessary.  Constructive knowledge is often much easier to prove than actual knowledge.  As an example, following a severe storm, a court may deem that reasonably acting property owners would inspect trees for broken branches among other dangerous conditions.  In this regard, it is important to note that intentionally avoiding the inspection of trees, among other things, and thereby choosing to remain ignorant of a dangerous condition may be deemed an act from which constructive knowledge is imposed.

Conclusion

The owners of trees, or those entrusted with the care and maintenance of trees on behalf of the owners, owe a duty of care to reasonably ensure that the trees are maintained.  If a person becomes injured or property becomes damaged by a tree that was improperly maintained, liability for the injury or damage may arise.