ANNUAL SOWTHISTLE, Sonchus oleraceus L. 1, top of plant in bloom; 2, seed. Annual, reproducing by seed. Stem smooth, erect, 1 to 6 feet (0.3 to 1.8 m) tall, with a milky juice. Leaves at base of stem more or less petioled; upper leaves clasping the stem with pointed projections; deeply cut, usually with a large end segment, margins with soft prickles. Flower heads about 3/4 inch (1.9 cm) across, of light yellow ray flowers; borne on numerous branches at top of plant. Found in gardens, pastures, wasteland, and roadsides.

 SPINY SOWTHISTLE, Sonchus asper (L.) Hill. Similar to the above. Annual. Leaves nearly entire, prickly-edged, stem leaves clasping the stem with large, rounded, earlike lobes.