Additional information on Wild Parsnip hazards, control and disposal is available on the Ontario’s Invading Species Awareness Program web site.
Wild Parsnip is an invasive plant that is increasingly common within the City of Ottawa in areas of uncultivated land, roadside ditches, nature trails, as well as on and surrounding rural and residential properties.
Wild Parsnip may pose a health risk to humans. The plant sap contains chemicals that may cause skin and eye irritation and make the skin prone to severe burning and blistering when exposed to the sun. The blisters typically occur one to two days after contact with the plant. This can result in long-term scarring of the skin.
The best way to avoid contact with Wild Parsnip is to become familiar with what the plant looks like so you do not accidentally get burned.
Identification
Wild Parsnip is a highly branched plant, with hollow green stems. It has two growth stages: non-flowering leafy rosettes at ground level and 0.5 to 1.5 metre-tall flowering plants. In the first year of growth, low-growing non-flowering rosettes of leaves form with a cluster of spindly, compound leaves that resemble celery leaves. Second and third year plants have tall, branched flowering stalks that usually bloom in early June to late July. Seeds are flat and round. It is a biennial plant, reproducing only by seed. The seeds can lie dormant for years making it even more challenging to control.
What to do if you see wild parsnip
On City property:
Report Wild Parsnip, Poison Ivy or Giant Hogweed on city property by calling 3-1-1 or letting them know using their on-line reporting form.
On Private Property:
Strategies to remove Wild Parsnip include the digging out the plant roots, targeted mowing, the use of herbicides and ongoing monitoring.
Digging the root up: Residents that have a small infestation in a yard or garden (fewer than 100 plants) or who do not want to use pesticides can dig out as much of the taproot as possible with a sharp shovel or spade. Follow-up digging will be required every few weeks to deal with re-growth (if the taproot was not completely removed) or missed plants. DO NOT burn or compost Wild Parsnip plants that have been cut down or dug up. Plants and roots that have been removed should be placed in a dark plastic bag and placed in the sun if possible away from areas children or pets could access them.
Targeted mowing: Mowing can be effective if begun just after peak blooming, but before the seeds set in the late summer or early fall. Cut plants will likely re-sprout after mowing, so it is important to combine mowing with other control methods such as bagging and removing the plants, especially those that are flowering and spot spraying with an approved herbicide. Be especially careful when using mowers, weed whips, mechanical string trimmers as they can spray users with sap and bits of the plants, leading to redness and sometimes hundreds of blisters on exposed skin. Wear goggles and protective clothing when mowing.
Use of herbicides: When a weed such as Wild Parsnip is declared a noxious weed, both the City and residents are able to purchase herbicides to control it. This is not considered a cosmetic use of pesticides because this plant can pose a risk to people. For more information please go to the Ontario Ministry of the Environment and Climate Change (MOECC) website.
Monitoring: Long-term monitoring is important in keeping this weed under control, as seeds will continue to germinate for several years.
