Wild Parsnip

Jul 21, 2011

by Lorraine Julien

Photo: Wild Parsnip courtesy Roy Lingen

The leaves and sap of Wild Parsnip can cause severe skin reactions when the plant is flowering, as it is now in July. Be extremely careful if you see this biennial plant growing along our roadsides and in other undisturbed areas. It looks very much like a tall Queen Anne’s Lace but the flowers are yellow rather than white. Wild Parsnip (Pastinaca sativa) grows about 2-5 feet tall and is a member of the Carrot family the same as dill, celery and caraway. This plant has a long, thick taproot that is edible.

The elimination of roadside spraying has assisted in the spread of this weed, which has now spread over most of North America. Wild Parsnip is tolerant of a wide range of conditions and soils; however, it does not like shade and prefers sunny areas.

The greatest concern is for people who gather wild flowers or those who use grass trimmers or other vegetation-clearing devices along roadsides. There’s a good chance they may not realize how dangerous this plant can be. After contact with sap from the leaves or stem, it takes about 2 days for a rash to appear. The sap reacts in sunlight, causing the skin to turn a purplish colour with boils filled with clear liquid forming underneath, as with a second-degree burn. It is extremely painful but not itchy. Scars from the burns and the purple discolouration could persist for years and you may have a hypersensitivity to ultraviolet light for a long time to come. If the weed comes into contact with the eyes, temporary or permanent blindness can result, though this doesn’t appear to have happened to anyone in our area yet.

If skin does come into contact with the sap, public health officials advise people to immediately seek shelter from the sun and wash the exposed skin thoroughly with soap and cold water. If done immediately following contact, the skin will likely not suffer burns.

The best way to control Wild Parsnip is early detection and eradication. If there are not many plants, a very effective method of control is to cut the entire root just below ground level with a sharp shovel or spade. Cutting below ground level prevents re-sprouting. In some soil types in wet conditions, you may be able to pull the plants out by hand as long as your arms and hands are covered.

Note: Use extreme caution and ensure that all exposed skin is covered (gloves and a long sleeved shirt). Burning does not seem to impact the plants themselves – they quickly regenerate. However, in the darkened soil following a burn, Wild Parsnip rosettes are easy to recognize and can be controlled by hand digging.

Note also that biennial plants do not flower until their second year so the first-year plants can only be recognized by their leaves.

Recent articles in the Kingston Whig-Standard and Westport Review Mirror reported the death of a 70-year-old man from Portland, Ont in late June . He had come in contact with Wild Parsnip and suffered severe burns to his hands and arms – so severe that he was admitted to hospital, where he died. In the past few years, he had suffered poor health and was in and out of hospital. Since this person had a weakened immune system, it would seem that the burns from Wild Parsnip may have contributed to his death.

Wild Parsnip was introduced to North America hundreds of years ago by European settlers who brought over a few plants to provide them with another source of food.

When researching Wild Parsnip, I came across several websites that provided recipes to cook it! Apparently it tastes very similar to parsnip from our gardens. The recipes included instructions for the root to be boiled and mashed, baked, cut in thin strips and deep fried, and also as a relish. The roots are harvested in late fall or early spring when the leaves are generally dead and withered or very small. At this time, there is very little sap and the hot, sunny conditions required for the rash to strike, do not prevail.

On a recent trip along Highway 7, I noticed Wild Parsnip growing along the roadside every now and then and it is abundant all along Road 38 from Kingston to Sharbot Lake.

If you think you have this weed growing on your property and you’re not absolutely sure that it really is Wild Parsnip, there is a lot of information on the Internet or you could contact your local weed inspector. They’re listed in the municipal pages of your telephone book. The accompanying photos are courtesy of Roy Lingen and are posted on the Verona Community Association’s website at www.veronacommunity.on.ca/misc/parsnips.shtml

Please feel free to report any observations to Lorraine Julien at This email address is being protected from spambots. You need JavaScript enabled to view it.  or Steve Blight at This email address is being protected from spambots. You need JavaScript enabled to view it.