Canada | Less and less green cities

Urban greenery in cities across Canada has declined by 8 percentage points between 2000 and 2022, according to the most recent environmental census conducted by Statistics Canada. In Quebec, Montreal has recorded the greatest setback, while the city of Saint-Jérôme is said to be the greenest in the whole country.

Montreal is grayer

In Montreal, urban greenery decreased by 9.3 percentage points for the periods from 2000-2004 to 2018-2022. The decline was particularly felt between 2015 and 2018. But the metropolis is no exception. According to the Statistics Canada study, the decrease was more marked in large urban centers such as Toronto (-11.7 points), Vancouver (-14.2 points) and Calgary (-16.5 points) for the same periods . The city of Milton, Ontario, recorded the worst decline in the country with a decrease in green areas of 30.5 percentage points.

Saint-Jérôme, the greenest

Conversely, the city of Saint-Jérôme is the greenest in Canada since 93.2% of its territory is made up of urban greenery. Sherbrooke arrives at 5^e row, with 90.6% green areas. “Green spaces are an asset that is greatly appreciated by citizens and investors,” underlines Marc Bourcier, the mayor of Saint-Jérôme. The municipality of Laurentides is crossed by the linear park Le P’tit Train du Nord and by the Rivière du Nord, itself lined with parks. “The Parc naturel du Lac-Jérôme is a park as big as the Parc du Mont-Royal. We are very proud of that,” added Mr. Bourcier. According to him, safety and green spaces are the two priorities that emerge most often when he surveys his population.

Elsewhere in Quebec

In total, 69.3% of the territory is classified as a green zone in Montreal, 87.7% in Quebec City, 86% in Trois-Rivières and 86.4% in Chicoutimi. Across Canada, 72% of the land area occupied by 1016 towns and cities was classified as green area.

Greenery against population growth

For Geneviève Cloutier, professor and director of the Planning and Development Research Center at Laval University, the decline of urban greenery is not surprising. “Urban growth competes with green spaces,” she notes. The professor says that climate change, with more frequent and intense heat episodes, is also making life difficult for plants. Invasive species and diseases also harm urban greenery. “The emerald ash borer, for example, was a formidable opponent in certain neighborhoods of Montreal and in Quebec as well,” she says. In Montreal, approximately 40,000 ash trees have had to be felled since 2012 because of the disease.

Greener, healthier

“It’s sad,” says urban planner Danielle Dagenais about this decrease. Sad because plants have many advantages in a society. “Greenery, and especially trees, is important for countering heat islands, for regulating the water cycle, and it’s essential for safeguarding all biodiversity,” she says. Plants also have a positive effect on mental and physical health and they have an aesthetic aspect, adds the professor from the School of Urban Planning and Landscape Architecture at the University of Montreal.

500,000 trees by 2030

In Montreal, Mayor Valérie Plante’s office argues that her administration recently created the Grand Parc de l’Ouest, “the largest municipal park in Canada,” and the Lachine Riverfront Park, two projects that will see the light of day in the next years. “We aim to plant 500,000 new trees by 2030. As for the most recent canopy index, it is at 25.4% at the scale of the agglomeration, thus exceeding the objective of 25 % by 2025. It should also be noted that the canopy index has increased by nearly 5 percentage points, whereas it was 20.8% in 2015”, indicated the office of the mayor in a written exchange. In 2021, 33,000 trees were planted and 40,000 ash trees were protected in Montreal.

Methodology

To measure urban greenery, Statistics Canada uses satellite images taken at different times of summer. The pixels of these images are classified according to a scale ranging from green to gray urban area and they make it possible to measure the photosynthetic activity. The data takes into account “parks and other green spaces and public and private facilities,” says Statistics Canada. Also, the “population centers” studied have at least 1000 inhabitants and have a population density of 400 or more inhabitants per square kilometer.