Herbs, to 2 m tall, often branched. Lateral roots with nodules to 2.6 cm in diam. Rhizomes with fibrous roots. Stems quadrangular, conspicuously winged, pith white. Petiole to 10 cm, conspicuously winged; leaf blade ovate to lanceolate, 5-25 cm, base cuneate, orbicular, or rarely shallowly cordate, margin serrate to double serrate. Thyrses terminal, to 30 cm; cymes 5-8-flowered; peduncle to 5 mm, glandular hairy. Pedicel glandular hairy. Calyx ca. 3 mm; lobes ovate, margin not membranous, apex acute to subacute. Corolla green, ca. 6 mm; lower lip with narrow middle lobe; upper lip slightly longer than lower, lobes orbicular, ca. 1 mm, with overlapping margins. Stamens ca. 2 X as long as corolla, exserted; staminode fanlike to obovate, slightly longer than upper lip, sometimes absent. Ovary ca. 2.8 mm. Style ca. 7 mm. Capsule globose-ovoid, 7-8 mm including short beak. Fl. Jul-Sep, fr. Sep-Nov.
Home