People heading out for a walk or bike ride along one of Toronto's most popular trails this week are being confronted by the shocking sight of drastic clear-cutting in what used to be a heavily-treed green space.

ET Seton Park — one in a chain of connected parks accessible from the Lower Don and other trails — now looks like a barren wasteland, and the public is wondering what the heck happened, how and why.

Anyone know why parts of the Don Valley Trail have been clearcut? This is near the Science Centre, but I've been seeing this since Pottery Rd. pic.twitter.com/wOldHfuWLU

— Jocelyn Lambert Squires (@JocelynSquires) March 12, 2024

Unfortunately, the removal of trees in the area is a necessary part of construction on the forthcoming Ontario Line subway, which will run east from Exhibition Place across the city, up Pape, and through Thorncliffe and Flemington Parks before its terminus at the current Ontario Science Centre.

While some are extremely distressed at the dramatic loss of so much mature local flora, others are considering it a fair trade-off for the benefits of new public transit infrastructure, albeit a very unsightly one.

Ontario Line clear cutting at ET Seton Park.
byu/TorontoBoris intoronto

One citizen called their recent trip along the trail "bittersweet," writing that "seeing the number of trees that have been cut down in the Don is a disappointment at minimum."

"I have no doubt the Ontario line will be a great option for thousands of Torontonians, but it feels like the planning didn't properly take into account the environmental impact to our city," they continued in an Instagram post, tagging Don Valley cleanup and protection organization 'Don't Mess With the Don.'

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A post shared by Chris Francato (@chrisfrancato)

Advocates from the group have been very vocal on socials in the last few weeks, mourning the loss of many rare decades-old trees that served as habitat for wildlife.

"Tragically, thousands of trees have been cut down and the life they held within, taken by chainsaws and machines. Felled without acknowledgement or ceremony and necessary recognition of their importance and connection to we humans and all of our relations in the Don Valley community," reads an Instagram post from the end of February.

Volunteers held a vigil over the weekend to honour the plants lost, which they called a "painful sacrifice" for the sake of the new line.

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A post shared by Don't Mess with the Don (@dont_mess_with_the_don)

In a Reddit discussion on the topic Tuesday, citizens said they were discouraged by the move, writing that "trees take decades if not a century or more to mature. Cutting them down, let alone a full clear cut, should be a completely last resort."

Others seem a bit more hopeful, with one person saying that the loss represents "a tiny amount of trees relative to how many the city has and worth the huge environmental benefits the subway will bring."

"As much as it pains me to see trees clear cut, the amount of emissions the line will save over time will be well worth it," one stated.

"The only thing we can hope is that they replant and appropriately repopulate the areas they've cut," added another, who also noted that the clear-cutting has long been part of the approved process for the work.

But, they acknowledged that adequate efforts to replace the lost trees with new ones "might be a high hope for Metrolinx."