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Perennial sowthistle

(Sonchus arvensis)

Perennial sowthistle is a perennial forb native to Eurasia. The plant's erect stems can grow 2 to 5 feet tall, they are hollow and have a milky juice that appears when the plant is injured. The plant branches near the top of the stem and will exhibit a showy yellow disc flower about 1 1/2 inches in size and resembles a dandelion. The flowers are borne out of bracts that are sticky and slightly hairy. Seeds are produced out of the flower bract and are red to brown in color, and have ribs that run lengthwise on the seed. The seeds are connected to a silky, parachute-like tuft of white hair and travel very easily in the wind. Leaves of the plant are alternate and clasping to the stem. The leaves vary in size generally getting smaller the higher up on the stem. Some leaves may be deeply lobed and have prickly margins. Perennial sowthistle grows from a deep taproot that exhibits horizontal rhizome-like roots that will produce other stems.

Perennial sowthistle fact sheet