Residents warned to stay away from colourful but toxic weeds now flowering in Ontario

They may look pretty, but Wild Parsnip and Cow Parsnip, now flowering in Oshawa and around southern Ontario, are toxic weeds that contain compounds that can burn the skin or eyes, becoming even worse when exposed to sunlight.

The plants look like colourful wildflowers often found along the edges of parks, open spaces, trails and roadsides until the autumn, but are a growing concern across Ontario and can pose a health risk to people and pets.

Symptoms typically occur within 48 hours and consist of painful blisters that may result in scarring. Though the plant does not attract the attention of most cats and dogs the sap may transfer to your pet if they are exposed and can be toxic if ingested.

Residents are reminded not to touch or pick the flowers from these plants. The best ways to prevent contact are to be familiar with the plants’ appearance and ensure you, your children, and your pets stay away.

Wild Parsnip

Wild Parsnip has yellow flowers that grow up to 1.5 m tall. The single stem of the plant is smooth and features leaves arranged in pairs with sharp, mitten-shaped leaflets.

Cow Parsnip

To identify Cow Parsnip, look for a 1 to 2.5 m. tall stem with a few purple areas and deep ridges with fuzzy hairs. The plant features white round flower clusters and leaves similar to maple leaves or an open palm with three fingers outstretched.