A pandemic DIY project takes root in NDG: measure your own backyard tree
MONTREAL -- Researchers at Concordia were stumped this spring when they realized that a normally straightforward activity was suddenly off-limits: knocking on people’s doors.
Biology professor Carly Ziter had been planning to spend the summer, together with research assistants, asking NDG residents for permission to go into their backyards and measure the trunks of their trees.
Montreal’s backyard trees are a mystery to scientists. Trees are vitally important to cities: they reduce flooding by absorbing excess water, cool the air during heat waves and even improve the health of people who live near them.
“People living in tree-lined neighbourhoods tend to have better physical and mental health,” says Ziter.
But not all trees do all those things in the same way, she explains—a big maple, for example, may cool the air more than a pine, but a pine brings unique bonuses of its own. A cherry tree or other fruit tree may not provide much shade, but it will help draw honeybees and birds, which are good for gardens.
“It’s not just ‘a tree is a tree,’ but different species of trees, different sizes of trees, will provide different kinds of benefits,” Ziter said.
Montreal’s publicly owned trees have been well documented—scientists know the ones growing in parks and on sidewalks. But they know almost nothing about the ones on private property, though they make up about half of the city’s trees, Ziter said.
Her Loyola-campus-based team wanted to map the trees of NDG. Now, since they can’t do it themselves, they’re asking locals to take a pandemic DIY approach, measure their own backyard trees and email them the details.
In fact, once the researchers switched to the “citizen science” concept, Ziter said, she realized she was “actually really excited” about it, saying “maybe we should have been doing this all along.” In the end, the bigger goal is to grow the right mix of trees around the city, which is something property owners can help with.
People in NDG who want to participate just need to send in two things: a measurement of their tree trunk’s circumference, using string, and photos of the tree—specifically of its bark, a leaf, and ideally a bigger overall shot of its shape. There is a worksheet available on the team’s website.
Trees are predictable enough that once the researchers use the photos to identify the species, they’ll be able to gauge its overall size from the trunk diameter, said Ziter.
Master’s student Kayleigh Hutt-Taylor is turning the project into her thesis, and along with two undergraduate research assistants, will be handling and analyzing the data when it comes in.
Ziter, who lives in NDG herself, says she’s hoping some people might be motivated to help by the ever-present need to keep kids occupied, and maybe even give them a ready-made science lesson.
“I think people are all at home right now, they’re looking for something to do,” she said. “They’re looking for activities for their children, in many cases—people who are home-schooling.”
As for what she thinks they’ll learn, Montreal is already facing a well-known tree crisis: many of its ash trees have fallen prey to the emerald ash borer, with tens of thousands already culled. Over the next few years, the city will have to try hard to replace that loss.
“It's not so much that there’s something particularly special about that ash tree as that there were so many of them,” Ziter explained.
“Several areas of Montreal had ash trees lining entire streets, and so we're looking at a situation where, in some neighbourhoods, it might be upwards of 25 or 50 per cent of the street trees were ash and will now be gone.”
Citizens can help by planting new trees on their property, but it’ll be key to know what kind of trees to plant, she said—the goal is “making sure that we replace those trees that we've lost, and to replace them with multiple species so that we don't run into the same situation again,” where a single pest can destroy such a huge number at once.
And that’ll mean having a tree map, she said.
“If you're planting a tree, maybe plant something that's different from your neighbour.”