By Lanny Englund, CUFN Pacific Representative
For those of us in the field of Urban Forestry, we are accustomed to the term canopy cover, which is typically defined as the percentage of ground covered by leaf canopy as seen from overhead. Canopy cover is an effective high level indicator for all of the human health, ecosystem services, economic and aesthetic values that trees generate for our cities. Communities that have analyzed their canopy cover and projected where it may be going typically find that this process highlights the need for action to increase or even maintain the current level.
In 2013 the City of Vancouver, British Columbia analyzed their canopy cover as part of the development of their Urban Forest Strategy. What they found was that their canopy cover had dropped significantly from 22.5% cover in 1995 to only 18% in 2013. As an Urban Forest professional in the nearby community of Coquitlam, I wondered how this could be in a City like Vancouver that had one of the more protection-oriented tree bylaws in the region. Upon further analysis, Vancouver found that 23,490 healthy mature trees were removed during these two decades and that half of all these trees were removed under the provision in their Protection of Trees Bylaw that allowed homeowners to remove one tree per year regardless of age, size or species. In 2014, in response to these findings, the City of Vancouver removed this provision from their bylaw to help slow the loss of canopy cover. In addition, the Urban Forest Management Strategy they are working on recognizes that to turn the trend around there will also need to be significant tree planting efforts. Specifically, they found that some gains were possible in their parks and on their streets, but the majority of the opportunity to increase canopy cover in Vancouver exists on private property.
Protection alone will not ensure sustained or increased canopy cover, particularly in growing communities. Protection measures are an important piece, but to successfully achieve canopy cover targets in the long term, you need to have a comprehensive approach that links tree removal to tree replacement and proactive tree planting programs that target both public lands and the area in most communities where the majority of the opportunities lie, private property. I applaud the City of Vancouver for taking a look at their current canopy cover, how it has changed, setting a goal and developing a comprehensive plan to achieve that goal. The more communities that take this path the closer we will be to achieving the national Canadian Urban Forest Strategy’s vision for all Canadian towns and cities, “A canopy of trees, sheltering and protecting our communities; part of a green infrastructure that promotes healthy air, clean water, habitat, quality of life and economic prosperity.”