Source: Karen Johnson UMN Extension Educator – McLeod & Meeker Counties
Wild parsnip, a noxious weed on the control list in Minnesota, has continued to spread throughout the state. Otherwise known as Pastinaca sativa, wild parsnip falls onto this list because of its characteristics. The Minnesota Noxious Weed Law (Minnesota Statutes 18.75-18.91) defines a noxious weed as “an annual, biennial, or perennial plant that the Commissioner of Agriculture designates to be injurious to public health, the environment, public roads, crops, livestock, or other property.” The control section of this list states that the weed must be controlled by “preventing the maturation and spread of propagating parts.”
According to the Minnesota Department of Agriculture, wild parsnip is an aggressive, monocarpic perennial that grows to four to six feet in height. Wild parsnip germinates from seed, spends the first year or more as a rosette. Eventually the plant bolts into a mature plant in the second year or later, flowers, sets seed and dies. The leaves alternate along the stem, are pinnately compound and consist of egg-shaped leaflets having saw-toothed edges. Leaves get progressively smaller near the top of the stem. Blooming from June to late August, flowers are umbels consisting of many small, five-petaled yellow flowers. The seeds are small, broad, oval, and slightly ribbed. The wild parsnip plant dies after setting seed.
Wild parsnip is most known for growing in ditches and rail right of ways. However, it has also been found in sunny areas along trails, pastures, waste areas, and unmaintained gravel pits.
Use caution when near this plant. Wild parsnip causes phytophotodermatitis- when skin comes in contact with plant sap in the presence of sunlight, it can cause severe rashes, blisters, and discoloration of skin. Appropriate protective clothing including gloves, long sleeves, and long pants should be worn and direct contact with the plant should be avoided. If sap comes in contact with skin, avoid exposure to sunlight, 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 5 years to significantly decrease the population. For more information on wild parsnip and how to control it, follow Minnesota Department of Transportation Noxious Weed List and/or Minnesota Department of Agriculture: https://www.dot.state.mn.us/roadsides/vegetation/pdf/noxiousweeds.pdf