The city of Ottawa wants 40% of its land to be covered with trees in the future, according to the new official plan – compared to 31% in 2017. But after the May deer and tornado in 2018 destroyed many thousands of trees in the area, it is unclear how soon this goal can be achieved.
As efforts to repair the canopy take shape in the coming weeks and months, and as climate change causes more powerful and frequent storms, more resilient wood cover is needed to better withstand them, foresters say. defenders of green spaces.
A detailed picture of the damage has not yet emerged, as cleanup continues after this latest storm, but it won’t be long before it materializes.
In 2017, a major assessment of the tree canopy was made for the entire region of the national capital, and a very detailed interactive map of the canopy was prepared, as it existed in the same year (the results were made public in 2019).
He showed that 31 percent of Ottawa is covered with trees, compared to 45 percent of Gatineau and 76 percent of National Capital Commission (NCC) land in and around both cities. NCC-controlled land is not included in Ottawa and Gatineau figures).
It so happens that the next detailed assessment – they are made every five years – is scheduled to begin this month with air travel, as long as the time helps, according to Jason Pollard, section manager at the Ottawa Forest Department.
Data collection and processing will take months (a combination of aerial imagery and lidar data that reflects everything on the earth’s surface), but when done, it will show us how devastating the roar and tornado were across the region, among other changes.
Windswept trees are still partially blocking the Goldfinch Drive in Canata on June 14, 2022 (Francis Ferland / CBC)
Some neighborhoods have lost many trees
The city of Ottawa covers a huge area, and an overall tree crown drop of as much as one percent would represent a “huge number” of destroyed trees, said Paul Johannes, chairman of the Greenspace Alliance in the Canadian capital. The organization urges the municipality to protect and expand the city’s tree cover.
But increasing the scale to study the heavily affected areas, Johannes said neighborhoods with about 50 per cent of the tree’s cover could reduce it by up to 20 per cent.
“I think we will see a lot of measurable impacts … because at the neighborhood level, it really had a big impact on those who were very affected by the gorge,” Johannes said.
“Clearly this is unprecedented. I don’t think we’ve seen anything like it before in terms of damage.”
Paul Johannes, chairman of the Greenspace Alliance in the Canadian capital, says tools to improve the city’s tree canopy are available, but more money is needed to support them and get more trees into the ground. (Francis Ferland / CBC)
Pollard called derecho “the most significant forest disturbance of decades,” with varying degrees of damage in each neighborhood.
Some of the worst-affected areas already had few existing tree canopies, according to a 2017 canopy estimate that was mapped by the Ottawa Neighborhood Survey to allow residents to search for tree-crown percentages specific to their neighborhoods. .
Only 15 percent of Navan and Sarsfield were covered with trees in 2017, for example, and Stitsville had a canopy of just 21 percent.
Blossom Park, Merivale Gardens and Greenbelt were also hit hard. They boasted some of the densest wood cover in the city – about 44, 52 and 40 percent, respectively – and could reduce those numbers.
What did some of the damage from the gorge look like?
This video with a drone shows great damage in the Blossom Park neighborhood in Ottawa after a strong thunderstorm that passed on May 21. (Video by David Johnson)
Researchers are expanding the damage zone of EF2 downward
Meanwhile, researchers at the Western University’s Northern Tornadoes project continue to assess damage to and around Ottawa after a gorge and have found that winds corresponding to the EF2 tornado cause much longer damage than originally thought.
Although there are no tornadoes in the city, an EF2 blast – with winds reaching approximately 190 km / h – hit the southeast on a trail that is now thought to be about 36 kilometers long and five kilometers wide.
The entire EF2 damage zone is now about 36 kilometers long and just under five kilometers wide, according to Western Northern’s Northern Tornadoes project. Yellow indicates periodic failure EF2, green indicates periodic failure EF1, and blue indicates intermittent failure EF0. (Northern Tornado Project)
The EF2 Periodic Damage Zone begins just east of Ottawa Airport around Blossom Park, continues east through rural Navan and Sarsfield, and ends past the Hammond community in neighboring Clarence-Rockland, Ont. Damages include paths with most trees broken or uprooted, outbuildings and silos, demolished and broken hydro poles.
The study also reported periodic damage from EF0 (104-137 km / h) and EF1 (138-177 km / h) over a much wider area of eastern Ontario and western Quebec.
They used satellite images taken just before and after the storm (May 18 and May 25) to study changes in the wood cover. Some dramatic differences can be seen in McCarthy Woods; the forest along the Rideau River on the west side of Ottawa Airport; wooded area between Frank Kenny Road and Delson Drive in Navan; and at the northeastern end of Mer Bleue Bog, among other places.
Researchers have created this map of tree crown damage, visible via satellite in southeastern Ottawa and beyond after the derecho. Each black X marks recognizable changes in the tree cover, and the red X indicates worse damage. (Northern Tornado Project)
Building a sustainable canopy in the face of climate change
Some patterns of what fell into the gorge began to emerge – many conifers (many spruces and large eastern white pines), as well as lindens, according to Pollard, the city forester.
Plans to replace the downed trees have not yet been made, and cleaning is still underway, Pollard said, but discussions will take place in the coming weeks and months.
“We may have to look for ways to increase the number of trees planted,” he said. “Once we go through this initial phase of removing dangerous trees, then we will have some time … to get staff to look at areas that need targeted planting efforts in response. We’re not there yet. “
Jason Pollard, manager of the Ottawa Forest Services Division, says Ontario’s forestry departments need to build more resilient shelters to withstand the effects of climate change. (Francis Ferland / CBC)
Replanting efforts will need to focus on strengthening tree canopies to better cope with more powerful and frequent storms, he added.
“Looking ahead, I think for every Ontario community forest organization … we all need to think about how to create a sustainable forest canopy in the face of climate change and tough weather,” Pollard said.
“This will include things like species diversity, but also diversity in … the age of the species and the age of the tree crown.”
It is really a matter of decades to restore the shed to what it was. – Paul Johannes, Greenspace Alliance of the capital of Canada
Johannes of the Greenspace Alliance said the city was moving in the right direction in recent years with tighter tree regulations and a relatively new forest management plan, but that more money was needed to survive these changes and plant more trees in The Earth.
“It’s actually a matter of decades to restore the shed to what it was. So … maybe, given that this is the kind of event that seems to happen more often, there should be better budget reserves created to deal more effectively with filling the canopy. ” said Johannes.
After derecho, a new challenge – how to make “more sustainable” forest canopies
Jason Pollard, a section manager in the Ottawa Forest Department, says a strong thunderstorm in late May has raised concerns about how to protect tree shadows from future weather.
How to change the trees
Want free tree seedlings to plant on a private property, perhaps to replace the one that fell during the storm? Ecology Ottawa is distributing 20,000 seedlings this year and has three events to distribute today and next weekend. After June, more gifts are planned for the autumn planting season.
The city of Ottawa is trying to plant about 100,000 trees in a normal year, according to Pollard. The spring planting season usually takes place between May 1 and June 30, but what is left of it was canceled after the storm to allow crews to focus on cleaning. All planned spring plantations have undergone autumn.
“Although the postponement of planting and the cancellation of events is disappointing, I want to assure council members that we will consider carefully how to restore forest cover in the community once the storm clean-up effort is over,” wrote Alain Gontier, the city’s general manager. . of Public Works, in a note dated June 1 to the council.
Arborists from the city of Ottawa are clearing fallen trees and branches in Aladdin Park in southern Ottawa near the airport on June 17, 2022, almost a month after the gorge on May 21. Crews are still focused on clean-up efforts and will later turn their attention to replanting efforts in heavily affected areas. (Jacques Corivo / Radio Canada)
In the parks, employees are compiling a list of significantly damaged trees to replace them in 2023 and beyond, according to the city.
Anyone who wants to replace a city tree in their property in front of the street or plant one where there is space can apply online to plant a tree from the city. It’s free, but there are conditions and criteria you must meet, including property owners being obliged to water newly planted trees …
Add Comment