Dangerous and invasive wild parsnip spreading in U.P.
GLADSTONE — Wild parsnip is a perennial with yellow-flowered umbels atop 3- to 5-foot tall stems. While it may be pretty to look at, people who touch the plant soon discover its less appealing trait. When the juices of the wild parsnip plant touch your skin and are exposed to ultra-violet light, they cause serious rashes, burns and blisters called “phytophotodermatitis.” The resulting skin discoloration can last several months. If you come in contact with wild parsnip and notice development of burns, cover the affected area with a cool, wet cloth and seek medical attention.
More and more of the plant is being found in the U.P.
Wild parsnip’s toxic compounds (called furanocoumarins) are found in the juices of its leaves, stems, flowers, and even fruits. Phytophotodermatitis will usually appear within 24 to 48 hours and is painful. In many cases, the blisters will lead to brownish pigmentation that can last for years.
According to Hiawatha National Forest’s East Zone Botanist, Stephanie Blumer, this invasive plant has become increasingly common across the Upper Peninsula.
“The key for outdoors enthusiasts,” she said, “is to learn to recognize this plant so that when you see it, you can avoid it.”
How can you recognize wild parsnip? While it looks similar to several other carrot family plants, the flowers of wild parsnip are yellow and the stem is smooth and green with very few hairs. Its leaves are long, saw-toothed, pinnately compound and form a basal rosette during the first year. The leaves are further divided into leaflets that grow across from each other along the stem, with two to five pairs of opposite leaflets. In its second year from June until mid-July, and sometimes even through late summer, the plant flowers. Its flowers are small and yellow with five petals and there are hundreds per plant. The flowers are arranged in 2-6 inch wide umbels at the tops of stems and branches, and there are usually no bracts, and very small or non-existent sepals at the base of the flowers.
“As wild parsnip spreads, more people are coming into contact with it,” said Deb LeBlanc, west zone plant ecologist for the Hiawatha Nastional Forest. She added that individuals who will be working, hiking, or involved in other activities around the plant can reduce the risk of exposure by wearing long-sleeved shirts, gloves, and long pants.
What are your chances of encountering wild parsnip? While it originates from Eurasia, wild parsnip has become a common invasive plant in U.P roadsides, ditches, and other disturbed open areas. (For instance, it is blooming now along US-41 between Rapid River and Trenary.) Believed to have been introduced to North America by early European settlers who grew it as a tap root; the wild populations are thought to be a result of escaped cultivated plants. Wild parsnip is a plant that inhabits various growing conditions such as dry, moist, and even wet-mesic prairies, oak-openings, and calcareous fens.
Once it invades open ranges, it begins to take over in waves and spreads rapidly, especially in disturbed areas. This invasive plant is spread through the distribution of its seeds that are carried by the wind, vehicles, equipment, and water. The seeds themselves, are typically large, slightly yellow, ribbed, flat, and round. It is around September through November that the plant will produce its seed and being a monocarpic perennial, once the plant seeds, it will die. However, the seeds can remain viable in the soil for up to four years, thus adding to the difficulties of eradicating the plants existence.
“Wild parsnip has been designated as a state noxious weed in approximately 35 states. “Besides the obvious health risk, the plant is problematic due to its ecologically invasive habit,” said LeBlanc.
For further information on Wild Parsnip contact your local U.S. Forest Service botanist at 906-387-2512, ext. 20, or 906-643-7900.