|A 4-8' plant with a smooth, hollow stem, purplish in its upper part, and often with a whitish bloom. The rough, lance-shaped, toothed, short-stalked leaves are in whorls, usually of 6. The small fuzzy flower heads have only pinkish-purple disc flowers and are in a large, dense, dome-shaped cluster at the top of the stem. Blooms July-September in moist, open places, roadsides, fields. There is a white variety, forma albidum.
The large, dense, dome-shaped cluster of flowers, the hollow stem and the whorls of 6 leaves identify this plant.