Project Blue - Roots & Shoots Canada Water Campaign

Urban Forests

Although almost half of Canada’s land is covered in forests, 80% of the population lives in urban regions where tree cover can be sparse.

Trees within a city, often referred to as the urban forest, can contribute a great deal to the image, health and quality of life of the cities in which they are found.

Check out the following facts to find out more about the benefits of urban forests.

Canada’s cities are about 19% forested. While this may seem significant enough, the amount of tree canopy (the percentage of leaf coverage of a city) recommended for a healthy urban forest is 35-40%, according to American Forests.

Urban air is often quite polluted because of emissions from motor vehicles, factories, power plants and furnaces. Trees clean the air. In particular, trees with large leaf-surface areas absorb nitrous oxides, sulphur dioxide, carbon monoxide and ground-level ozone, which are contributors to air pollution.

Cities are prone to large amounts of storm runoff (excess water that cannot be absorbed by soil) because of the abundance of paved roads and other impermeable surfaces that cover the natural terrain. Runoff carries pollutants into local water bodies and causes soil to erode more quickly than it would naturally. Trees and their roots help keep our water clean by retaining large amounts of water and reducing erosion and runoff.

Trees provide shade in the summer and serve as a shelter from the wind in the winter. This helps to reduce energy needed to heat and cool buildings.

Studies show that trees in the city have a number of less obvious benefits. For instance, the presence of trees can improve the aesthetic image of an area and help build stronger, safer communities. Additionally, green settings have psychological benefits, including improving concentration in children with attention-deficit hyperactivity disorder (ADHD) and improving recovery rates and times for hospital patients with window views of trees.

Urban trees suffer from a large amount of stress because of poor soil quality, air pollution, drought and damage from construction, making them more vulnerable to disease and pest infestations.

Trees are often removed from city locations because they can interfere with power lines, water pipes or other city infrastructure. However, these sorts of problems can usually be prevented by carefully selecting tree-planting sites.

Sources

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