I have previously written about the giant sequoia in the 2300 block of West 41st that was cut down after nearly a century of living in the middle of the Kerrisdale commercial area. Over the years development on the block was setback in order for the tree to flourish, which it did for many years.
One of the Price Tags commenters is the thoughtful urbanist Alex Botta who provides some more insight into this giant of a tree living on a commercial street. In his response, Alex details why we SHOULD be having a conversation on what is an appropriate street tree, and outlines what happens when a tree is simply too big or unwieldy for a public boulevard location. We’ve printed Alex’s comments below.
“Of course this tree was stressed. It was the wrong species for the urban environment, and was subjected to an inadequate development approach at its periphery. There was little thought given to the requirements of the root area, the primary criteria being space and depth. The best solution would have been to create a park around the tree decades ago, because it truly is a giant parkland species wholly inappropriate for tight streets.
Inappropriate tree species and maintenance practices is an ongoing problem. The legacy will be the removal of too-large trees in tight urban sites in future, especially boulevard strips. Lifting sidewalks and broken curbs and retaining walls are everywhere. There is a 1.5 metre diameter Platanus in the boulevard just outside of my house and late one Friday night its roots plugged the ancient city sewer under the road. City Engineering earned their pay that evening and unblocked the line within 10 minutes with a mean-looking root eater attachment to their roto rooter. Eighty years ago the tree was likely misidentified as a maple (similar leaves) and was planted with hundreds of maples, the occasional plane towering above all the other trees.
Urban trees should be planned early, along with the zoning. Small and medium-sized trees with special attention to the root zones are most able to adapt to imposed urban pressures and spaces. Most trees will take drought (dropping leaves early is a protective response during stress), but compounding that is the typical planting plan that does not allow for optimum and healthy soil conditions. A 1.2 m x 1.2 m continuous trench in a boulevard filled with quality growing medium, subsurface deep root vault structures, and in some cases structural soil (organic soil with uniform diameter broken rock to allow compaction and root growth in the spaces between the rocks) are the second best current practices for urban forest health. They afford a continuous underground volume of growing medium for the conjoined root masses and often have watering ports. Temporary automated irrigation is another important step tp assist in establishment. Vaulting is made from recycled plastic and can take the weight of paving and vehicles over top, making them ideal for plazas, downtown sidewalks and parking lots.
The best practice is to plant trees in parks (especially large trees) while ensuring good soil health.
Dirk Brinkman brought up the fascinating idea to use Sequoia and larch as replacements for the devastated pines in the Interior. I would add that the native Sequoiadendron sempervirens (Coast Redwood) of California is dying out due to climate change and could be planted as part of a refuge in coastal BC. Most of the varieties currently planted here are giganteum and are pretty ubiquitous as ornamental trees.
In addition, any silvicultural effort to mitigate climate change MUST include a change in our provincial forestry management structure that has resulted in too many cases of extinction logging. Community forest trusts run by local municipalities with beefy Forestry Departments would be a good model to test, according to foresters like Ray Travers.”