By Katherine Gathje, Interim Extension Educator
Wild parsnip is a noxious weed on the control list in Minnesota. It has continued to spread across the state over the past few years despite efforts to slow or stop the spread. Wild parsnip is one of the weeds on the list that are enforced by the Minnesota Noxious Weed Law which mandates that the weed must be controlled by preventing the maturation and spread of propagating parts. The sale, transportation, and propagation of the plant is not allowed, and is enforceable by counties or local municipalities.
The plant is native to Europe and Asia and was brought to North America and grown as a root vegetable. Wild parsnip has escaped from cultivation through the years and is now commonly seen in ditches and along railroad tracks. It may also be found along trails, pastures, waste areas, and in unmaintained gravel pits.
The Minnesota Department of Agriculture describes wild parsnip as an aggressive, monocarpic perennial that grows four to six feet in height. The wild parsnip lifecycle starts with the plant germinating from seed, it spends the first year or more as a rosette. The plant then bolts into a mature plant in the second year or more; it flowers, sets seeds, and dies. The leaves alternate along the stem of the plant and consist of egg-shaped leaflets with saw-toothed edges. Leaves get smaller closer to the top of the stem. You can find wild parsnip plants blooming from June to late August. The flowers are recognizable by their 2-6 inch wide flower clusters that contain many small, five-petaled yellow flowers. The seeds are small, broad, oval, and slightly ribbed. Wild parsnip plants will die after setting seeds.
It is very important to use caution when near this plant. The chemical properties of wild parsnip cause phytophotodermatitis. This means that, when skin comes in contact with plant sap in the presence of sunlight, it can cause severe rashes, blisters, and discoloration of the skin. Wear protective clothing including gloves, long sleeves, and long pants when working around the plant, and direct contact with wild parsnip should be avoided. If sap comes in contact with skin, be sure to avoid exposure to the sun, immediately wash skin with soap and water, and seek medical attention.
Wild parsnip, as well as other noxious weeds, needs to be persistently managed over a span of up to five years to significantly decrease the population.
For more information on wild parsnip and how to control it, follow the Minnesota Department of Transportation Noxious Weed List and/or Minnesota Department of Agriculture at www.dot.state.mn.us/roadsides/vegetation/pdf/noxiousweeds.pdf.