Smooth sowthistle (common sowthistle, milk thistle)
Sonchus oleraceus

Annual, lactiferous, seed-propagated weed with strong, cone-shaped taproot. S. oleraceus produces latex and is a preferred feed for birds, chicken and geese.

Flower heads light yellow to greenish yellow (Sonchus arvensis: intensive yellow). Leaves and stems contain milky sap. Soft, floppy, shiny, greasy, bluegreen leaves.

Young Plant: Round, often flatly sinuate in front, light green, entire, petiolate.

Stems: Erect, thick, ramified, up to 80 cm-100 cm (2.62 - 3.28 ft) high.

Leaves: First leaves nearly circular, with fine teeth; following leaves runcinate-pinnatifid or undivided, soft, blue-green, enclosing the stalk sagittately, prickly dentate.