Round two of wild parsnip maintenance in Ottawa parks begins next week
Posted Aug 8, 2026 10:15:29 AM.
Last Updated Aug 10, 2026 11:29:43 AM.
Following a second round of mapping, the city’s parks maintenance and forestry services are continuing to treat and control wild parsnip growth starting August 10.
The first round of mapping and treatment took place in June, with 71 parks and hydro corridors receiving a treatment of Glyphosate and 65 storm water management facilities receiving a treatment of Navius Flex.
In the second round of treatment, 185 parks, hydro corridors and stormwater management facilities are scheduled to receive treatment of Glyphosate or Navius Flex.
Glyphosate is the most widely used herbicide in the country, and is a critical asset in weed management, the government’s website notes.
“Pesticides must be approved by Health Canada’s Pesticides Regulatory Directorate…before they can be imported, sold, or used in Canada,” it reads. “Pesticides are subject to rigorous science-based assessments by Health Canada scientists before being approved for use in Canada.”
The treatment will last about one week to cover all identified areas. To reduce disturbances to parks and as per the Ontario Pesticide Act, only locations deemed to have a moderate to high level of wild parsnip infestation and a high risk to the public will be spot sprayed with Glyphosate.
In other areas, lower levels of infestation will be mowed or pulled by hand. Where spraying occurs, residents can expect to see wilting or discolouration in two to four days. The full impact of the spray could take up to 20 days and contractors will indicate spray locations with signs, removing them once complete.
The parks service is also responsible for wild parsnip in storm water management areas and hydro corridors. The herbicide Navius Flex will be applied in those areas, and people should start seeing the early effects within a few hours and the full effect after several weeks.
Residents should expect to see crews of eight in the proposed locations, equipped with backpack-style sprayers.
Wild parsnips can pose risk to humans as its sap contains chemicals that may cause skin and eye irritation and make the skin prone to burning and blistering when exposed to the sun, causing long-term scarring.
Learn more about how to identify wild parsnips through the below photos.
