Wildflowers Found in Oregon

Prickly Sow Thistle

Sonchus asper - Locally common, all summer, perennial, 15-60 in. Erect with both flowering and nonflowering stems. Milky sap. Leaves entire to pinnately lobed; lower leaves 3-6 in., with short petioles. Upper leaf edges with thorny teeth, clasping stems; lowest lobes extend beyond stem and curl. Flower stalks much divided, leafless. Flower heads 1-2 in. across, containing yellow ray-like disk flowers. Grows in wet to damp soils, Noxious weed. Nonnative.