Perennials or subshrubs, 50-150 cm. Stems erect, hispidulous to coarsely short-pilose. Petioles 0 or 0.5-1(-3) mm. Leaf blades linear-lanceolate to elliptic-lanceolate, 1.5-7 × 0.4-1.2 cm, margins denticulate to subentire. Heads usually 5-50+ in (terminal or lateral) corymbiform arrays. Involucres cylindric to campanulate, 5-6 mm. Phyllaries in (3-)4-5 series, apices of the inner ± spreading (pinkish purple, hyaline, petaloid, slightly expanded, truncate). Corollas light blue to purplish or reddish. 2n = 50. Flowering Aug-Nov. Open woods, edges of fields and woods, roadsides, fencerows, ditches, other disturbed sites, flood plains, bottomlands, along streams; 0-50 m; Fla., La., Miss., Tex.; Mexico; West Indies; Central America; South America.