LATE EUPATORIUM, Eupatoriurn serotinum Michx. 1, lower portion of plant with roots; 2, upper portion of plant in blossom; 3, flower head; 4, seed. Perennial, reproducing by seed. Roots shallow, fibrous. Stems hairy, erect, 3 to 6 feet (0.9 to 1.8 m) tall, upper portion much branched. Leaves narrow, tapering to a point, petioled, edges toothed; upper leaves alternate, lower ones opposite. Flower heads small, cylindrical, of whitish disk flowers only, borne in a compact, flat-topped cluster at top of plant. Seed narrow, oblong to oval with several longitudinal ribs and with a tuft of whitish bristles at top. Found on moist soils in feedlots, old pastures, and wasteland. A number of other somewhat similar species of Eupatorium (e.g., E. perfoliatum, E. purpureum, E. altissimum, E. maculatum) are found in the region, under the common names of thoroughwort, boneset, or joe-pye weed. They are all more or less similar to this illustration. In several states, one or more of these are much more common than E. serotinum.