London Plane trees in my backyard

(Question)

What is the best way to manage these fast growth trees? And what is the best way to prune them? We cannot enjoy our yard in summertime due to their toxic seeds and want to take them down but the city says they’re too big.
What if I were to replace them? I planted them as they were recommended by our landscape architect but after thirteen years we realize they were a poor recommendation. Thus, a poor choice.

Thank you.
Denise Wright Ryback.

(Answer)

Thank you for contacting the Toronto Master Gardeners.

London Plane trees, Platanus x acerifolia or Platanus x hispanica, have been widely used in many cities around the globe for their remarkable resilience to urban pollution.  They are thought to be a hybrid between the American Sycamore and the Oriental Plane and are very hardy trees which can live to be several hundred years old.

Indeed, they are somewhat messy trees and seem to be constantly dropping something or other on the garden below but squirrels and birds nest in their tall branches, finding a home.  Tree roots can be extensive, thick and tough, and in the right circumstances, can easily find their way into sewage or water pipes and easily raise paths or driveways.

The city of Toronto has very strict rules regarding removal of any trees, whether on private property or not and fines for unlawful removal can be hefty.  It is best to work through official channels with your own certified arborist should you want to go down this route.

The other option is pruning.  In many cities, London Planes are regularly pruned to control their size and debris waste.  This can be in the form of annual minor pruning to reduce the canopy and allow more air flow or more drastic pruning in the form of pollarding.

As your trees are only in 13 years, contacting a professional arborist immediately to come up with a plan for going forward is imperative.  If these trees are annoying you now, they won’t be any better in 5, 10 or 15 years time.

Also it’s prudent to be aware of the negative respiratory health impacts of pruning plane trees while they are in leaf. This is because in this state plane trees release a significant amount of fine dust and volatile organic compounds (VOCs) that can be hazardous to respiratory systems.

Hope this information is helpful.