With a new bylaw and more ambitious planting targets, Peterborough hopes to end the carnage in its urban forest
Will Pearson  - 
May 13, 2021

On Monday night, city councillors gave preliminary approval to a new bylaw that would regulate the removal of healthy trees on private property, requiring at least three replacement trees be planted for every healthy tree removed. Under the plan, property owners would be responsible for planting one of the replacements, and the City would plant the other two.

Councillors also gave preliminary approval to hiring a full-time technologist to oversee a boost in municipal tree-planting initiatives and incentives. There’s also a recommendation to include annual funding for the City’s share of replacement trees in the capital budgets starting in 2022. That funding could work out to be more than $1 million per year, a staff report states, depending on how many replacement trees are needed.

This new bylaw comes as Peterborough’s urban forest faces alarming rates of decline. In just five years, the city’s urban canopy coverage has decreased by 10 percent. 

Last summer, the city’s overall canopy coverage was measured to be 26.8 percent. The draft Official Plan sets a goal of achieving 35 percent canopy coverage by 2041.

Peterborough’s goal is to increase canopy coverage over the next two decades. Lately, we’ve been going in the wrong direction. (Source: City of Peterborough.)

The City of Peterborough already plants hundreds of trees on public property every year to replace ash trees infected with the emerald ash borer, trees removed to facilitate construction projects, and trees that die naturally, according to the City’s manager of infrastructure management Michael Papadacos. These programs on public land will continue, he says.

But the majority of our community’s trees grow on private property, which is where bylaws like this one come into play. Incentivizing citizens to plant trees and take care of them, while discouraging citizens from removing trees, is seen as essential to preserving the urban forest that we have left.

“We need our citizens to help us big time with this one,” said Coun. Lesley Parnell on Monday night. “We need people to realize that the trees on their private property aren’t just a major asset to themselves … but an incredible asset to the entire city.”

How we got here

In 2017, two bylaws were passed to help protect Peterborough’s urban forest. The Woodland Conservation Bylaw applied to forested areas that are bigger than one hectare, while the Tree Conservation Bylaw applied to smaller properties.

At the time, staff estimated that 43 percent of Peterborough’s urban forest was situated on just 250 properties that were 5 acres or larger, while 28 percent of the urban forest was situated on smaller properties. (The remaining 30 percent or so was on publicly-owned land.)

The Woodland Conservation Bylaw has remained in effect since 2017. It does not permit healthy trees to be removed from a woodland without a development agreement stipulating how the developer will achieve the same amount of canopy coverage as was present before the removals.

But the Tree Conservation Bylaw, which applied to smaller properties, was met with significant opposition calling it too restrictive, confusing and difficult to administer. It was repealed in March 2019.

Since then, a permissive interim bylaw has been in place that only requires property owners to notify the City whenever they cut down a tree.

During this two-year interim period, at least 2,323 healthy trees that would have been regulated by the Tree Conservation Bylaw have been removed, depriving Peterborough of more than 32 acres of canopy coverage and releasing an estimated 1,002 tons of carbon, according to a staff report released last week. Only 10 percent of property owners who removed these trees expressed an intention to replace them, the report stated.

If city council gives final approval to the new bylaw later this month, it would come into effect in July and replace the interim bylaw that is currently in effect.

How the urban forest fights climate change

Peterborough’s urban forest is considered a “key asset” in our local plan to mitigate and adapt to climate change. Last year, studies were carried out to assess the extent of the forest and the environmental benefits it provides.

The 650,000 trees currently estimated to be growing within the city’s boundaries store 130,000 tons of carbon and sequester an additional 4,100 tons every year, according to one of the studies cited in the staff report

For comparison, the entire community of Peterborough produced 349,743 tonnes of carbon in 2011, according to baseline calculations done for the city’s Climate Change Action Plan. Peterborough’s goal is to reduce our carbon emissions to at least 30 percent below that 2011 number by 2031. (A progress report is expected later this year.)

A massive red oak on Aberdeen Avenue starts to put out its leaves this spring. Trees are remarkable pieces of natural infrastructure. They capture and store carbon, absorb stormwater and cool our neighbourhoods. (Photo: Will Pearson)

In addition to sequestering and storing carbon, trees also absorb water, which helps to reduce the amount of runoff that enters the watershed. Runoff increases the risk of water contamination and flooding.

The same study found that Peterborough’s urban forest mitigates 43,000 metres cubed of stormwater runoff every year. It also removes 84.5 tons of pollutants from the watershed each year.

Lastly, the urban forest has a cooling effect — something that is likely to become even more important as temperatures continue to heat up. In addition to cooling our streets, trees cool our buildings, and that can reduce the need for air conditioning.

In their report introducing the new tree bylaw, city staff estimate how much it would cost to achieve these environmental benefits through engineered solutions instead of letting the urban forest work its magic. Their answer? The annual carbon sequestration, energy savings and pollutant removal Peterborough’s urban forest provides is worth $1.9 million per year. 

Meanwhile, the 130,000 tons of stored carbon Peterborough’s urban forest has accumulated over the years, if released, would cost $13.5 million to eliminate through other means.

What’s in the new bylaw?

If passed, the proposed bylaw would go into effect on July 9, 2021. It’s meant to correct some of the perceived overreach of the 2017 Tree Conservation Bylaw, while still providing a framework that will allow our community to maintain its urban forest.

One common complaint about the 2017 tree bylaw was that it required a city staff person to inspect every tree prior to removal to determine whether it was healthy or not and how many trees would be required to replace it. This proved to be too time-consuming, and led to significant delays, according to staff. 

If passed, the new bylaw would allow professional arborists to issue permits directly to their customers. The plan is also to give arborists access to a mobile app they can use to share information with the City from the field, which could also make administration of the bylaw easier.

Tree removal permits will cost $50 if issued through a licensed arborist, and $150 otherwise.

The new bylaw also shifts to a model of shared responsibility for replanting trees after removal, with the property owner responsible for one replacement tree and the City responsible for two.

Unlike the 2017 bylaw, the new one would only apply to the removal of trees and not to pruning them.

Will this work?

After going more than two years without any formal requirements to replace trees that are removed from non-woodland private properties, this new bylaw will almost certainly be an improvement in terms of maintaining the urban forest.

But it also has its limitations, and should be considered one part of a more comprehensive plan.

For example, the new bylaw applies to less than half of Peterborough’s urban forest, with the rest either regulated by the Woodland Conservation Bylaw or situated on public property.

The bylaw proposes replacing only healthy trees — but tree mortality is depleting the urban forest even faster than the removal of healthy trees, according to projections provided by staff last year.

According to this projection from last year, tree mortality is a bigger threat to our canopy coverage than the removal of healthy trees. (Source: City of Peterborough)

One big challenge in implementing the replanting strategy will be finding appropriate public land for the purpose.

One of the next steps outlined by staff is to identify what municipal lands are available for the kinds of large-scale tree-planting projects that will be required to fulfill the City’s share of replanting. Boulevards and other street-adjacent locations are often used to plant trees, but those locations can bring additional stresses that hinder growth. With the exception of parks, private properties are often the most conducive locations for healthy trees.

As Vern Bastable, the manager of GreenUP’s Ecology Park and the former coordinator of GreenUP’s urban forestry program told Peterborough Currents last summer, “People always look to the city for answers to this, and the answers are really in people’s backyards.”

“We can’t do this forever with just municipal lands,” Papadacos says. “I suspect we’re going to have to be looking at other stewardship or partnership programs with large property owners or institutions.” 

When planted on boulevards, trees are often cut back to make room for powerlines, like this one on Sherbrooke Street has been. (Photo: Will Pearson)

While members of the City’s Environmental Advisory Committee expressed support for the new bylaw in January, they did flag that the proposed $500 fine for non-compliance might not be steep enough to change behaviour.

Lastly, the new bylaw, like many other municipal urban forestry initiatives, focuses only on replacing lost trees, a strategy that will never achieve our goal of actually increasing the city’s tree canopy.

Still, this bylaw does come with a staff recommendation to significantly boost capital spending on municipal tree planting initiatives starting in 2022, which ought to greatly increase the number of trees the City can plant. Councillors have been given fair warning that there could be over $1 million in new spending to approve in next year’s budget deliberations. Tree-loving citizens should watch capital budgets in the future to ensure sufficient funds are committed to keep up with the replacement strategy.

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