A strategic and sustainable planting approach for Montreal
In the current context of global changes, urban forests are facing many stresses and diseases. Yet they provide many essential services to fight climate change and contribute to the health and well-being of citizens. In response to this growing challenge, the City of Montreal has committed to planting 500,000 trees on its territory as part of its 2030 Climate Plan.
In 2021, the David Suzuki Foundation commissioned us to carry out a study aimed at optimizing the planting of these 500,000 trees. Using socio-economic and ecological indicators, our team is proposing a planting strategy that maximizes the sustainability of the urban forest and improves the distribution of nature in the city. Through this study, we propose a methodological basis that can be adapted to the realities of each territory. Our aim is to support Canadian municipalities in implementing a planting strategy that meets today's challenges.
Our study addresses three overarching questions associated with the implementation of tree planting as a climate change adaptation measure in municipal areas:
Where is it possible to plant?
Where should planting be prioritized to address issues of social equity and climate change resilience?
Which tree species should be favoured according to the constraints of the territory to ensure the sustainability of the urban forest and the maintenance of ecosystem services?
Number of trees to be planted in priority on the territory
"The functional diversity of Montreal's urban forest is currently very low (3.7/9), which means that it is at risk of dying out in the face of climatic and biotic threats. Our analysis shows that it could reach 8.2/9 if the selection of species to be planted is strategically planned."
Fanny Maure, Scientific Director
The maximum potential planting area varies by borough, so the number of trees to be planted will vary by location. Some boroughs can accommodate more trees than others. Rivière-des-Prairies-Pointe-aux-Trembles would be the borough that could theoretically accommodate the most trees (almost 135,000)!
Recommendations
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The analysis shows that more than 60% of the total area available for planting is located on private land. It is therefore essential to put in place strategies, subsidies and programs that encourage planting on these private lands. The study also shows that more than a third of the total area available for planting in non-mineralized areas (which makes tree planting less expensive) is located on residential land. Planting trees in these areas would allow residents to benefit from ecosystem services directly.
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The approach used in the study allows for the integration of several ecological criteria, but also social ones. Indeed, it is important to measure the social as well as climatic weight when prioritizing tree plantations. A prioritization based on resilience and equity is essential to meet the needs of each district according to their level of socio-economic vulnerability. In other words, it is essential to consider social aspects in planting strategies and not only ecological aspects.
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Diversifying the species that are more resistant to the different constraints of the Montreal territory would increase the functional diversity index to 8.2/9. Montreal's urban forest would then be very resilient and would reduce the risks in the face of future global change threats.
Press release
MONTREAL | TERRITOIRE TRADITIONNEL KANIEN'KEHÁ:KA NON-CÉDÉ, Monday, November 28, 2022 - The David Suzuki Foundation, in collaboration withHabitat, publishes a report entitled Increasing equitable adaptation to climate change: Scenarizing the planting of 500,000 new trees on the territory of the City of Montreal, which aims to identify where to plant the 500,000 new trees promised by the City of Montreal to accelerate equitable climate adaptation. The first steps in planting more than half of these trees will be taken in six designated boroughs.
