TALL IRONWEED, Vernonia altissima Nutt. 1, upper portion of stem; 2, flower head; 3, single flower; 4, seed; 5, distribution. Perennial, reproducing by rhizomes and seed. Roots strong, fibrous. Stems erect, 3 to 6 feet (0.9 to 1.8 m) tall, widely branched in the upper portion. Leaves long, lanceolate to narrowly ovate, sharply toothed, with short hairs on the lower surface. Flower heads about 3/8 inch (9 mm) across, numerous, surrounded by smooth-tipped leafy bracts, borne in a flat topped cluster at the ends of the branches. Disk flowers reddish-purple. Seed mostly oblong, prominently ribbed, with short bristles at the tip. Found in meadows, pastures, and wastelands.

 WESTERN IRONWEED, Vernonia baldwini Torr. 6, flower head; 7, distribution. Similar to the above species. Leaves densely hairy on lower surface. Flower heads surrounded by bracts with hooked tips. Found in prairie pastures.