Canadian hemlock (Tsuga canadensis)

Nice to meet you!

I’m a majestic and iconic tree found mainly in the boreal and temperate forests of Canada and the northern United States. I’m an evergreen conifer with a conical shape. My bark is brownish-grey and peels off in thin strands. I can grow to an impressive height, sometimes over 40 metres!

I’m a remarkably hardy tree, and I play a crucial role in forest ecosystems. My ability to live hundreds of years, sometimes even more than a millennium, is a testament to my resilience and ability to thrive in a variety of conditions. My dense foliage provides shelter and protection to many species, and my cones contain seeds that feed squirrels, birds and other animals.

Why the greening team loves the Canadian hemlock:

We chose it for its important cultural value. The Indigenous peoples of Canada have long used its durable and resilient wood to build their homes, canoes and other useful items. Its resin can be used as an adhesive and to make traditional medicines.


This summer, I and the other trees in planters in the Quartier des Spectacles accomplished these feats:

  • Our transpiration helped cool the air by the equivalent of 1.30 cumulative degrees Celsius per day
  • Our leaves helped filter gaseous pollutants equivalent to a total of approximately 2.027 mg of ozone

I had a great summer in downtown Montreal! Here’s how I and the other trees in the Quartier des Spectacles spent our time:

  • We spent an average of nine hours a day contributing actively to cooling and cleaning the air
  • We rested for an average of nine hours a day
  • We spent about five hours a day in a protective mode: we closed our stomata to avoid losing any of our stored water

Help us identify our potted trees! Click here to suggest a name.


Air cooling:  

Did you know that trees transpire through their leaves? If you attach sap-flow sensors to the tree trunks, you can calculate the cooling effect of the trees. You just need to compare the surrounding temperature to the impact of the tree’s transpiration and shade. Isn’t that impressive?  

The elimination of pollutant gases: 

Trees are our best allies in the fight to eliminate pollutant gases! Thanks to sensors attached to the tree trunks, we can measure the amount of ozone that is absorbed by the leaves via their stomata (the cells that allow a plant to breathe, transpire and photosynthesize).

Why are we collecting this information?

The Quartier des Spectacles Partnership and its greening team have placed 93 trees in planters around the Quartier des Spectacles. The goal is to make downtown Montreal greener and more resilient in the face of climate change.   To optimize its greening initiatives, the Partnership is collaborating with a specialized team and various academic partners. Two research projects are currently underway, in collaboration with UQAM. One of the studies focuses on how trees cope in the high-stress conditions of a city centre, while the other explores the impact of trees on the well-being of the population.  

Click here to learn more about the research projects on the potted trees at the Quartier des Spectacles.