Herbaceous, monocarpic perennial. Grows as a rosette with upright leaves, persisting for at least one year. Flowering stems are stout, hollow, grooved and up to 5’ tall.
OverviewOther names for this plant include:
- Common names: parsnip
- Scientific names: P. sativa var. pratensis
- Invades prairies, oak savannas and fens as well as roadsides, old fields, and pastures.
- Broad habitat tolerance; grows in dry, mesic, or wet habitats, but it does not grow in shaded areas.
CAUTION: When sap contacts skin in the presence of sunlight, it can cause severe rashes, blisters, and discoloration of the skin (phytophotodermatitis). Wear gloves, long sleeves and long pants when handling.
Classification in Wisconsin: Restricted
Species Assessment Groups (SAG) were assembled to recommend a legal classification for each species considered for NR 40. The recommendation for wild parsnip was based upon this literature review developed by the department.
Leaves: Rosette leaves are pinnately compound with 5-15 broad, ovate to oblong leaflets. Stem leaves are alternate, with 2-5 pairs of opposite, sharply toothed leaflets. Petioles wrap around the stem. Upper stem leaves are reduced to narrow bracts.
Flowers: Numerous, small, 5-petaled, yellow flowers in umbels 2-6” wide at the tops of stems and branches. Blooms from late spring to mid-summer.
Fruits & seeds: Seeds are flat, round, yellowish and slightly ribbed. Seeds remain viable in the soil for four years.
Roots: Long, thick taproot.
Similar species: Wild parsnip can be confused with two native prairie species -- golden Alexander (Zizia aurea) and prairie parsley (Polytaenia nuttallii). Golden Alexander is shorter and its leaves have only 3-7 leaflets. Prairie parsley leaves have few teeth and its flowers are rounded, not flat like wild parsnip.
Mechanical: Cut root at an angle 1-2” below the soil surface. A brush-cutter can also be used for large populations before seeds set. Remove flowering heads and dispose of in a landfill or by burning.
Chemical: Spot treat rosettes with 2, 4-D, metsulfuron-methyl or glyphosate. Spot treat adult plants mid-May to mid-June with metsulfuron-methyl plus a surfactant.
For more information on control techniques, visit the Wild parsnip factsheet by University of Wisconsin-Extension.
View wild parsnip pictures in our photo gallery!