perennial sowthistle USDA PLANTS SYMBOL: SOAR2
Sonchus arvensis L.
Synonym(s): field sowthistle, creeping sowthistle, field sow-thistle

Sonchus arvensis is a perennial herbaceous plant. Stems can reach 4.9 ft. (1.5 m) in height and contain milky sap.
Leaves are sessile, alternate, clasping, up to 12 in. (30.5 cm) long and decrease in size further up the stem, margins undulate with sharp spines.
Flowering occurs in June to October, when yellow, tight, dandelion-like flower heads develop at the tips of the branches. Flowers open 2-3 hours after sunrise and close about noon.
Fruits are reddish, ribbed and have a tuft of hair at the top.
Ecological Threat
Sonchus arvensis occurs along roadsides, railroads and other disturbed habitat. It is native to Eurasia.

Identification, Biology, Control and Management Resources