Description from Flora of China
Acrocephalus fruticosus Dunn.
Shrubs 15-30 cm tall. Stems robust, twisted, brown, glabrous, much branched, bark exfoliating longitudinally; branches slender, white floccose-pubescent. Petiole to 4 mm; leaf blade elliptic-oblong to oblong, 0.8-2 cm × 2-5 mm, herbaceous, densely floccose-pubescent, sparsely golden glandular, base cuneate, margin crenate, apex obtuse. Spikes capitate, terminal, 5-10 × 4-8 mm, long pedunculate, white pubescent; verticillasters compact; bracts subulate, ca. 2 mm. Pedicel less than 1 mm. Calyx campanulate, ca. 2 mm, white pubescent outside; teeth lanceolate, subequal, sparsely puberulent inside; fruiting calyx tubular, slightly constricted at throat, ca. 3.5 × 1 mm, scarious. Corolla green or white to purplish, ca. 4.5 mm, pilose outside, hairy annulate inside; upper lip circular, ciliate; lower lip dilated, middle lobe circular, slightly concave; lateral lobes oblong. Nutlets chestnut brown, obovoid, apex rounded, base acute, ca. 1.2 mm. Fl. and fr. Sep-Nov.
* Dry, sunny, weathered gravelly areas; 2000-3000 m. Sichuan, Xizang, Yunnan.