Mature Plant

Description: Perennial sowthistle is a perennial reproducing by seed and underground roots. Roots can penetrate the soil to a depth of several feet. The mature plant will reach a height of 3 to 7 feet. The upright stems are smooth, with or without hair, and contain a milky juice (latex). The leaves are variable in shape and size. The basal leaves are narrow and deeply lobed. The leaves along the stem are 4 to 8 inches long, alternate and attached directly to the stem, irregularly toothed, lobed, with spiny edges. Flower heads are approximately 1 1/2 inches in diameter, produced in clusters, bright yellow, and attached to terminal branches at the top of the plant. Flowering occurs in June through August and seeds mature in July through September. The seeds are reddish-brown, 1/8 inch in length, slightly flattened, longitudinally ribbed with 5 to 7 ribs and have smaller cross wrinkles.

Seedling

Distribution: Perennial sowthistle will grow in cultivated fields, pastures, waste areas, and along roadsides. Perennial sowthistle is found throughout Minnesota with the heaviest infestations found in the western and northern half of the state.