Description

Key Characters:

Growth Form: Coarse perennial herbs 8–20 dm tall, sometimes somewhat woody toward base.

Stems: Stems usually weakly erect, intricately branched, very sparsely puberulent.

Roots:

Leaves: Leaves simple. Opposite. Blades elliptic to broadly elliptic or ovate, 4–8 cm long, 2–4.5 cm wide. Apex acute. Base cuneate. Surfaces glabrous or occasionally lower surfaces with very few scattered hairs usually along the veins and margins; blades membranous; upper surfaces rugose. Margins sharply and coarsely serrate, the teeth conspicuously divergent. Petioles 0.5–2 cm long. Stipules absent.

Flowers: Flowers in indeterminate spikes, spikes slender, rachis flexuous to erect or somewhat nodding, 14–40 cm long, ca. 2.5 mm in diameter, the furrows somewhat shallow, nearly as wide as the rachis; bracts lanceolate, ca. 7 mm long, persistent. Flowers bisexual (perfect). Calyx narrowly tubular, 5-toothed and 5–ribbed, ca. 7 mm long, the teeth subequal. Corolla usually dark purplish blue with a paler center, the tube 7–8 mm long, imbricate. Stamens 2, included in corolla tube, staminodes 2; anthers dithecal, opening by longitudinal slits; anthers dithecal, opening by longitudinal slits. Ovary superior, 2-celled, placentation axile; ovules 1 per cell, attached laterally, erect, anatropous; style elongate, filiform; stigma terminal.

Fruit: Schizocarps dry; oblong–linear; splitting at maturity into 2 hard cocci; enclosed by the persistent calyx. Seeds 1 per fruit; linear.

Ploidy:

Habitat: Shaded; mesic; disturbed sites.

Elevation Range: 15–200 m.