July 27, 2006 at 7:37 a.m.
Wild parsnip is a member of the carrot family. It spends its first summer as a rosette of leaves fairly close to the ground. The plant is anchored in place by a long, thin taproot. When conditions are right, usually in its second summer, it sends up a single flower stalk that holds hundreds of yellow flowers in flat-topped, umbrella-like clusters called umbels. The flower stalks can grow to be from four to six feet tall. The leaves alternate on the stem with 5-15 egg-shaped leaflets along both sides of a common stalk. The leaflets are sharply-toothed or lobed at the margins with the upper leaves smaller. The flowers are broad flat-topped clusters from two to six inches wide with wide, numerous five-pedaled yellow flowers. The flowers bloom from June to late summer.
The seeds are small, flat, round, slightly ribbed, and straw colored. There are many seeds that take about three weeks to ripen before they can reseed and the seeds can remain viable in the soil for four years. The taproot is long and thick.
I didn't have wild parsnip in my asparagus, but rather Queen Anne's lace, which can easily be confused with wild parsnip. Queen Anne's lace can either be a flower or a weed. Many gardeners have it in their flower beds, but since it is so invasive, it soon becomes a weed.
Queen Anne's lace is in the carrot family also, and is known as wild carrot. This is because the leaves look like carrot or basil leaves. The main difference between wild carrots and wild parsnips are the color of the flower cluster. Remember, the color of wild parsnip is yellow while wild carrot is white. If this isn't confusing enough, consider that the taproot of the wild carrot is long and white and looks like a young parsnip.
What makes wild parsnip so dangerous is that it is one of a few plants that can cause phyto-photo-dermatitis. What it means is that chemicals in the juices of this plant with the help of ultraviolet light can burn your skin. These chemicals are found in the green leaves, stems and fruits of the wild parsnips.
The chemicals in the plant are absorbed by your skin and energized by ultraviolet light, causing a breakdown of cells and skin tissue. This leaves you with a red, sunburn-like area. Once exposed, your skin will turn red within 24 to 48 hours. In many cases, after the skin reddens, blisters appear and some of them quite large. Sometimes the area that was burned takes on a dark red or brown discoloration that can last for as long as two years.
In mild cases, skin reddens and appears sunburned for a day or so. In more severe cases, blisters form a day or two later. When they rupture, the skin begins to heal. In one article, I read where on person had the blisters heal only to have them return a year later.
The best way to get rid of wild parsnip is by finding it early in its invasion when there aren't many plants. Cutting the root of each plant just below ground level can help stop the spread. This can be done with a dandelion-digging fork, a sharp shovel or spade. If the population is large, a power brush-cutter is sometimes used. Regular mowing or grazing by cows, keeps wild parsnip from flowering and making seeds. If you're going to be near this invader, be sure to wear gloves, long-sleeved shirts and pants.
IN YOUR YARD AND GARDEN: Water trees and shrubs in the landscape. They need one inch of water per week. Water stress can make insect problems more pronounced so it's important to scout for insect problems in your yard.
Ash flower gall infestations are extremely heavy this year. They cause clumpy green growth on the ash trees. These galls turn dark brown later. Treatment is not advised.
It's too hot for anything special in lawn care. Grasses are too stressed for post-emergence weed control, so leave the weeds alone. Don't fertilize right now. We're in a holding pattern until mid-August when the lawn repair season starts. Focus on adding water. Apply 3/4 of an inch at 7 to 10 day intervals.
UPCOMING CLASSES: If you haven't received our fall class series brochure, call 651-674-4417 to have one mailed to you. It is also available in the 'Hot Topics' box at: www.extension.umn.edu/county/chisago. The series will include classes on food preservation.
PLANT CLINICS: Volunteer Master Gardeners will be available Mondays from 4-7 p.m. at the Extension Office in North Branch at 38780 Eight Avenue to answer your gardening questions.
You can also call 651-674-4417 during these hours to speak with a Master Gardener.
Samples can be dropped off during the day on Monday if you cannot stop in during clinic hours. Please note MONDAY is the only day you can drop off samples, as there is no longer staff at the North Branch Office who can answer gardening questions.
VOICE MAIL: You can leave a question for a volunteer Master Gardener at 651-674-4417. Depending on the volume of calls, they try to respond within a couple of days. During office hours ask for the Master Gardener voicemail, after hours, select ext. 18. You can also get your question answered on the web at: www.extension.umn. edu/askmg.