Battling Climate Change in Toronto: Every Tree That Survives is a Miracle

Issue: 
May-June 2007

THE SECRET WEAPON in the city’s battle against climate change is growing in Amanda McConnell’s front yard. Six trees – birch, red bud, willow, two giant maples and a serviceberry – crowd a space shorter than the fading hopscotch course scratched on the sidewalk out front. If it weren’t for the cars, telephone wires and a man across the street yelling at his girlfriend, you would think you had walked into a forest. “There wasn’t a tree when I moved in 18 years ago, so you see what can happen,” says McConnell. “I thought I’d be dead by the time they grew. In fact, the maple is as tall as the house.“

Te’re all going to have to take a gardening lead from McConnell if Mayor David Miller’s plan to double the tree canopy is going to succeed. His goal, announced last week as a central part of the city’s plan to confront climate change, is to increase leaf cover to 34 per cent of the city’s area from 18 per cent by 2020.
It seems like a no-brainer. Trees shield us from the sun. They soak up rain from severe storms. They filter pollution from the air, including carbon dioxide – the most potent greenhouse gas.

“We could kill people in an epidemic or a heat wave, or we could grow trees,” says Toronto city councillor and long-term environmentalist Gord Perks.

But it’s just not that easy. Trees take a long time to grow, especially when they’re planted in tiny plots of soil surrounded by slabs of concrete.

“It has taken 100 years to have what we have today. To double it, realistically it will take another 100 years,” says Richard Ubbens, the city’s chief forester.

The city’s new goal came as a surprise and he says he wasn’t consulted. Miller’s environmental point person, Mary MacDonald, says the plan is “not impossible,” but will take a lot of partnerships from the public. “It’s possible planting trees may catch the imagination of the public.”

City life is hard on trees. Their roots, smothered in cement, compete with pipes for space. Their branches are snarled by hydro and phone wires. They are often planted in dead soil, bathed in pollution and salt, and bashed by cars and lawn mowers.

“Every tree that survives is a miracle,” says Eva Ligeti, the province’s former environment commissioner.
Most don’t last more than 10 years on major roads, Ubbens says, by which point they’re little more than signposts.

Global warming is going to make survival even tougher. Forecasts for Toronto include violent storms that can break their branches and heat waves that will leave them parched. Doubling the canopy is a type of insurance. That way a severe drought or infestation by a pest such as the long-horned beetle won’t be as devastating.

“If that happens when the city only has 17 per cent canopy, the loss is fairly substantial. If the canopy is 30 to 40 per cent, even with that kind of loss, you still have a substantially green city,” Ubbens says.

To double the stretch of branches, his staff will have to triple the number of trees they plant every year from around 60,000 to 175,000, he says. He figures it will take 12 million trees over the next few decades. Even then, within a few years they would run out of public space. About three-quarters of the city’s land is privately owned and most of it is found in neighbourhoods such as Rexdale and the Annex, where McConnell lives. On average, only 19 per cent of neighbourhoods are covered by trees. That leaves a lot of planting space. For the city to meet its target, that’s where it must aim, Ubbens says.

How can the city compel people to plant?

City lawyers are delving into the City of Toronto Act to see if it could require people to plant in their yards, for one.

The city’s former tree advocate, deputy mayor Joe Pantalone, thinks the city should give free trees away instead. But given the current budget woes, handing out millions of $30 trees free seems unlikely.

University of Toronto urban forestry lecturer Andy Kenney thinks grants or tax incentives are the answer.

“If I’m going to spend money on trees in my backyard, why shouldn’t I get support to do that?”

Planting is only half the battle. To survive, a tree must be rooted in love and attention. The city has learned that planting a tree that hasn’t been ordered can spell early demise – in one case, 10 per cent of trees were uprooted after angry calls from citizens, and others were neglected.

An upcoming report on urban forests by the Clean Air Partnership shows it takes five years for a city tree to absorb all the carbon dioxide that’s gone into putting it there.

To get the full benefit of a tree, its crown has to stretch at least six metres, which can take as long as 20 years for some species, says Kenney.

“We need big trees in the city,” he says. “To double the canopy, you have to make sure we’re not losing the canopy in the first place. If you’re losing large trees and planting small trees, you’re not gaining anything.”

That’s what has happened last decade. In 1992, trees covered 22 per cent of the old City of Toronto – 5 per cent more than today. Then came the lean Harris years of government downloading and cutbacks, followed by the housing boom.

“Trees don’t give political donations. They don’t vote. They don’t go to demonstrations,” deputy mayor Pantalone says.

Learning its lesson, city hall has turned over a new leaf. It has boosted the forestry budget for more care and planting to $20.3 million, prohibited the destruction or damage of trees on private property without a permit, and introduced new building standards asking developers to cover 40 per cent of residential gardens with trees or shrubs. A new streetscape manual – calling for eight to 15 times the amount of soil per street – should extend their lifespan by at least 10 years, Ubbens says.

Staff are using new techniques too. They’re planting more from seed rather than using grafts, so each tree is genetically unique. That makes it less likely all will be felled by the same disease or infestation.

Other tactics include planting in clusters so trees protect one another, like in a forest, and diversifying species. Whereas 60 per cent of street trees in the past were quick-growing Norway maples, now they make up less than 30 per cent. In their place are oaks, red buds, ash, honey locusts, even species from the south like the Kentucky coffee tree and Ohio buckeyes. Southern trees might be more comfortable in heat waves. It doesn’t take long sitting in front of McConnell’s house to think she may have a solution. Trees erupt from the small patches of earth in front of most houses on her street.

“They have to harness the power of neighbourhoods,” she says about city hall. “They have to engage community organizations.”

Fifteen years ago, McConnell was sitting in a neighbour’s backyard when the buzz of chainsaws interrupted the quiet. They decided to hire a forestry student to survey trees in a five-block area. McConnell and her friends formed a group called Grassroots Albany, and asked neighbours about planting large trees. Planting days sprang up. A 2004 survey showed the area had 15 per cent more trees just as other areas were losing theirs.

“Local community forestry works. It may be the only way we can start adding and conserving the city’s canopy, because the forestry department can’t do it,” says the retired documentary writer.

“You start to think differently about the web of life around you.”

Listen to her talk about the autumn blaze stretching before her front porch and you’ll quickly admire it too for shielding her bedroom from the sweltering heat of summers. The pussy willow by her back window glows silver in January, reminding her of approaching spring. The serviceberry tree’s buds have already started to emerge. So lovely, you might just want to plant one in your own yard.

— reprinted with permission from The Toronto Star, March 31, 2007. Catherine Porter, Environment Writer, Toronto Star

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