Ottawa City Council’s Environment and Climate Change Committee met on September 16th to discuss the most recent Tree Canopy Mapping. Here’s what you need to know.
What is a Tree Canopy Mapping?
A Tree Canopy Mapping describes the distribution of tree coverage across an area. In Ottawa, City staff analyze canopy data every five years to monitor the impact of tree canopy change over time, as required by the City’s Tree-Planting Strategy. The Tree-Planting Strategy is the main activity of the second Management Period of the City’s Urban Forest Management Plan (UMFP), whose goal is on preserving, planting, and increasing Ottawa’s urban forest. The Tree-Planting Strategy under the UMFP is the City’s plan for achieving Ottawa’s 40% urban canopy coverage goal.
Why is Tree Canopy Mapping Important?
Trees are essential to our environment to provide oxygen and combat climate change.
Hence, Tree Canopy Mapping is an essential process to ensuring the health of Ottawa’s ecosystem. It is done to identify priority areas that need more tree coverage and determines Ottawa’s progress to achieving its 40% coverage goal. Canopy Mapping also provides crucial information for City staff to determine what factors can cause damage to Ottawa’s urban and rural forests—for instance extreme weather events, construction, forest health, and natural aging.
The data collected also allows Ottawa residents to hold the City accountable for their commitment to achieving 40% canopy coverage.
It’s in everyone’s interest that we have a healthy tree canopy, given the many benefits associated with trees. These include:
- Increased access to shade, which can act as a cooling resource to combat rising temperatures due to climate change
- Improved air, soil, and water quality
- Absorption of water during flooding events
- Erosion prevention
- Air filtration
- Carbon sequestration
- Food and habitat to animals and birds
So how are we doing?
Visualization of Ottawa's tree canopy in 2022.
The report determined that there has in fact been a 21.5% to 20.6% decrease in the tree canopy within the urban boundary, although the City observes that this is within the margin of error.
The report also offers a breakdown of canopy coverage per ward. As the report indicates, the increase in tree canopy in some wards is due to the growth of existing trees. The decrease in tree coverage in urban areas, furthermore, can be attributed to extreme weather events such as the tornado in 2019 and the 2022 derecho, land cleared for construction, the use of harmful pesticides, and natural tree mortality.
So in general, we’re doing okay with tree preservation, but we’re behind on tree planting.
More specifically, Table 2 included in the memo shows the results of the 2017–2022 report assessing how close each ward is to Ottawa’s 40% goal. The table indicates that almost all wards fail to reach the 40% canopy coverage goal. Only 3 out of 24 wards hit the 40% goal, and 14 wards had an absolute decrease in canopy coverage.
Next Steps
The 2% city-wide increase from 34% to 36% is great, but the decrease in urban areas needs to be addressed quickly. Ottawa needs more trees to combat the effects of climate change, including the kinds of extreme weather events that are becoming more frequent in Ottawa. If we keep neglecting to grow out urban tree canopy, we’ll also lose the benefits tree canopy offers.
With only 3 of 24 wards meeting tree canopy coverage goals, it’s time to recognize the seriousness in the lack of urban canopy coverage.
One way to address the pressing need is to fund community groups. Many community groups, such as Fôret Capitale Forest, and more community associations, are ready to help out and plant more trees, but they require funding.
Additionally, the City needs to stop sprawling, or greenfield development. This will help to maintain mature trees and the ecosystem. This year offers an opportunity to address precisely this, as the City revises its growth targets as part of its scheduled review of the Official Plan.
Finally, the Council needs to invest in the UMFP. City staff have cited lack of resources as a challenge to the implementation of the UMFP. As staff report, various staffing constraints—especially a low staff capacity—has made it difficult for staff to focus on multiple projects at once.
The City of Ottawa is not acting urgently enough when it comes to increasing tree canopy coverage. Ottawa needs more tree canopy to combat the seriousness of the climate crisis and support our ecosystem.
