Opinion: Why Edmonton needs to protect trees on private property, too

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Trees play a vital role in enhancing air quality, supporting biodiversity, and reducing urban heat effects. In light of the urban planning committee’s recent agenda on tree management, we strongly urge Edmonton city council to consider implementing a private tree bylaw, similar to the public trees bylaw enacted on May 1, 2022.

This initiative should be paired with promotional and educational programs to raise awareness among Edmontonians about the importance of protecting
both public and private trees. Our recommendation is based on three key arguments supported by years of experience and research.

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First, approximately 60 per cent of Edmonton’s trees are on private property, according to our calculations. Without regulations, these trees often go unmonitored and are at risk of removal or neglect. Edmonton’s current tree canopy covers about 13 per cent of the city, and only four out of 15 districts reach
a canopy cover of 20 per cent — a target the city aims to achieve over the next 50 years. Areas with less than one-per-cent canopy cover are often industrial zones, commercial areas, or new residential neighborhoods on the city’s northern and southern edges, while mature neighborhoods and those along the river valley generally enjoy higher canopy cover (i.e. more than 30 per cent). Significant efforts, such as the city’s ambitious goal of planting two million trees by 2035, will not be fulfilled by public trees only.

Second, there is a limited amount of public space available to support the additional trees required for this goal, and the supply of saplings cannot meet the demand within this short timeframe. Climate change and increasing tree diseases are also shortening the lifespan of common Edmonton tree species, including elm, spruce, ash, pine, maple, aspen and poplar. For example, the deadly Dutch elm disease has been recently identified in Edmonton and poses a significant
threat to urban forestry. This necessitates the replacement of existing trees alongside new plantings. In other words, public trees alone are insufficient to help the city meet its canopy goals.

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Our research team at the University of Alberta modeled the impact of trees in both residential and industrial areas in Edmonton, showing that increased canopy cover notably reduces the urban heat island (UHI) effect. Boosting vegetation cover by up to 20 per cent could lower UHI intensity by around 30 per cent, while a 30-per-cent increase in cover could reduce UHI intensity by nearly 40 per cent.

As tree coverage grows, we can expect further cooling of surface temperatures and reduced summer energy costs. While our model showed limited carbon sequestration compared to the city’s emissions, the cooling benefits are substantial.

Third, Toronto offers an excellent example. In Toronto, around 55–60 per cent of land and 60 per cent of trees are on private property, similar to Edmonton’s figures. Toronto’s canopy cover, currently about 28.4 per cent, has consistently increased with a target of 40 per cent within the next 25 years.

Recognizing that a significant portion of trees are on private land, Toronto has made private-property engagement a priority. The city offers grants and incentives to encourage tree planting and care on private properties, aiming to plant 120,000 trees annually. Additionally, Toronto, in partnership with other agencies, provides tree planting services to private landowners, covering up to 90 per cent of planting costs and supplying native trees and shrubs. In Toronto, any development permit application requires a tree permit if there is potential for tree injury during construction. Nearby municipalities, including Vaughan, Mississauga, Markham, Richmond Hill, and Brampton, have adopted similar policies. Edmonton council could draw valuable insights from these practices.

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Edmonton city council has consistently demonstrated its commitment to environmental and climate priorities. We encourage the council to continue its leadership by incentivizing tree preservation and planting on private property and by establishing a private tree protection bylaw. Trees don’t distinguish between private and public land; these boundaries are human constructs, not a part of nature.

Let us all root for all trees to make our city more environmentally resilience and sustainable growth.

Sandeep Agrawal is director of the Alberta Land Institute, associate dean, Faculty of Graduate and Postdoctoral Studies, and professor, School of Urban and Regional Planning at the University of Alberta.

Nilusha Welegedara is a postdoctoral researcher at the Urban Environment Observatory Lab and research manager at the Alberta Land Institute, University of Alberta. 

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