Description from Flora of China
Galeopsis bifida var. emarginata Nakai; G. tetrahit Linnaeus var. bifida (Boenninghausen) Kudo; G. tetrahit var. parviflora Bentham.
Stems erect, 20-60(-100) cm tall, robust; nodes enlarged when fresh, shrivelled when dry, bristly; internodes bristly, appressed pubescent, apically sometimes also glandular pubescent. Petiole 1-2.5 cm, pubescent; stem leaf blades ovate-lanceolate or lanceolate, 3-8.5 × 1.5-4 cm, adaxially appressed bristly, abaxially sparsely puberulent, glandular, base attenuate to broadly cuneate, margin crenate-serrate, apex acute or acuminate. Verticillasters solitary, crowded; bracts linear to lanceolate, 3-6 mm, base ± membranous, margin bristly, apex spinescent. Calyx ca. 1 cm, spreading bristly outside, puberulent inside; teeth subequal, almost as long as tube, narrowly triangular, apex long spinescent. Corolla white and/or yellow, rarely purplish red, ca. 1.4 cm, tube ca. 8 mm; upper lip obtuse, margin denticulate, bristly; middle lobe of lower lip oblong, ca. 2 mm wide, emarginate, purple spotted to margin, slightly constricted at base; lateral lobes oblong, entire, slightly wider than middle lobe. Filaments pubescent toward base. Nutlets brown, obovoid, triquetrous, scaly. Fl. Jul-Sep, fr. Sep.
A widespread weed.
Forest margins, roadsides, field margins, grasslands, waste areas, open thickets; 0-4000 m. Gansu, Guizhou, Heilongjiang, Hubei, Jilin, Nei Mongol, Qinghai, Shaanxi, Shanxi, Sichuan, Xizang, Yunnan [Japan, Kyrgyzstan, Korea, Mongolia, Russia; Europe, North America].