Gardeners call for more help, less bureaucracy in battle against invasive plants

CBC

29-05-2025

On an overcast day in the Kilborn Allotment Gardens (KAG), Jeff Hoyle points out the garlic mustard's distinctive white flowers. He's a gardener and a former agricultural chemist with a keen eye.
This plant is sprouting from a compost pile, but it can also be found across this large swath of public land, in gardeners' plots and below nearby treelines.
Janet Mark Wallace, another gardener, points out dog-strangling vines a few metres away, growing under a handful of buckthorn trees.
Buckthorn, dog-strangling vine and garlic mustard have one thing in common: They're all considered invasive species in Ontario because they harm the native ecosystem.
"It's problematic in that it does kill off all of the plant life, or tends to choke out plant life that's indigenous," explained Hoyle.
He's been gardening in the allotment for three years, and Wallace for even longer. Both have watched these species flourish.
"There's much more buckthorn than when I moved in 20 years ago," Wallace said. "You can see that there's trees dying because they're surrounded by buckthorn."
Invasives aren't just plaguing community gardens in the city — they're representative of a citywide problem, according to Coun. Marty Carr.
"So much of our expansive green space all over Ottawa has been overrun," she said.
To fight back against their spread, she wants the city to launch a more substantial effort to mobilize volunteers.
"The city could make a lot of gains. We are really behind all the other municipalities," Carr said.
'Everywhere, absolutely everywhere'
Under the Ontario Weed Control Act, the City of Ottawa is only responsible for taking "some action regarding the control of" only three invasive species on its property: wild parsnip, poison ivy and giant hogweed.
But during the COVID-19 pandemic, many residents offered to help eradicate invasives themselves, Coun. Carr said. The City offered them legal agreements to do the work on public property.
As demand grew, the city appointed a forestry stewardship co-ordinator to review the volunteers' plans and check that they had insurance, according to Carr.
One of the agreements, for the land restoration committee of the Alta Vista Community Association, includes the green space around the KAG.
But invasive species continue "slowly creeping in," said the chair of the committee, Michelle St-Germain, because the work is painstaking and labour-intensive.
"I've seen it everywhere, absolutely everywhere," she said.
City staff perform an assessment of the KAG each year at the start of the gardening season, according to a statement attributed to Dan Chenier, general manager of the city's recreation, cultural and facility services.
Buckthorn was identified on the perimeter of the KAG in 2024, he wrote, but there are no plans to remove it because it does not pose a "significant issue" in garden plots.
However, CBC did observe other invasive species inside garden plots during one visit. The city did not respond to a question about whether staff had identified other invasive species in the area.
Groups like St-Germain's have taken up their shovels to make a difference anyway.
She and the group's other members mostly focus on eliminating dog-strangling-vine, then plant and maintain native species in its place. But St-Germain said she's seen other invasives in and around the KAG, including buckthorn.
"There is hope in getting something accomplished, but initially it could be very discouraging," she said.
More volunteers could be contributing, Carr said, if the city wasn't holding them back.
One of the existing groups sent her an email in mid-May, frustrated because they still didn't have their renewed agreement for the upcoming year.
"We could have been mobilizing volunteers [in that time], removing invasive plants. It's the slow bureaucracy. We only have that one co-ordinator to do all that work," she said.
"When there are people in the community who have significant amounts of expertise in identifying, removing invasive species, who can mobilize the volunteers, who can educate the public and who want to do this work, I think that we owe it to them to give them a program."
'Turning community members into experts'
The model Carr suggested to city staff is used by Toronto Nature Stewards, a group run by the City of Toronto, which recruits and trains volunteers. The volunteers then work without direct supervision to monitor and remove invasives and plant native species in their place.
Programs like that are a "powerful way of making change in the community," said Carleton University biology professor Joseph Bennett. He studies invasive species and the most effective ways to control them.
"Having grown up near Ottawa, I have seen lots of invasive species increase over the years," he said. "Ideally, we are turning community members into experts and experts into people who are more in touch with the community."
Hoyle said if the city co-ordinated a program, he thinks he and others like him would be willing to volunteer to train others in their communities. He noted it's especially important to him because some invasive species have native look-alikes.
Bennett agreed that training would be an important component, to ensure people identify the right plants and also understand the best ways and times of year to remove them.
"Just even learning about something for an hour can save hundreds and hundreds of hours in terms of the efficiency of removing invasive species," he said.