16. Boehmeria tricuspis (Hance) Makino, Bot. Mag. (Tokyo). 26: 387. 1912.
八角麻 ba jiao ma
Boehmeria platyphylla D. Don var. tricuspis Hance, J. Bot. 12: 261. 1874; B. japonica Miquel var. platanifolia Maximowicz; B. maximowiczii Nakai & Satake; B. platanifolia Franchet & Savatier.
Subshrubs or herbs perennial, simple or few branched, 0.5-1.5 m tall; upper stems and branchlets densely pubescent. Dioecious or monoecious. Leaves opposite or rarely alternate, subequal in size; stipules lanceolate, 7-10 mm; petiole 1.5-6(-10) cm, densely pubescent; leaf blade dark green or black when dry, oblate to 5-angled or oblate to orbicular-ovate, often ovate in upper stems, 8-12(-18) × 7-14(-22) cm, papery, secondary veins 2 pairs along midvein, abaxial surface densely pubescent along veins and veinlets, adaxial surface roughish, densely strigose, base truncate, subcordate, or broadly cuneate, margin coarsely 8-12-dentate, teeth gradually larger distally, often biserrate apically, apex 3-cusped or lobed, tip serrulate. Glomerules on axillary spikelike flowering branches, male branches often branched, 8-17 cm; female spikes distal, unbranched or branched, 5.5-24 cm. Male flowers 4-merous, sessile; perianth lobes elliptic, ca. 1 mm, strigillose, connate at base. Fruiting perianth rhomboid-obovoid, compressed, ca. 1.2 mm, smooth, strigillose on shoulder, base cuneate or stipitate, apex with short neck, 2-toothed. Fl. Jul-Aug, fr. Sep-Oct.
Forest margins, thickets, along streams in hills and mountains; 500-1400 m. Anhui, Fujian, S Gansu, Guangdong, Guangxi, Guizhou, W Hebei, W Henan, Hubei, Hunan, Jiangsu, Jiangxi, Shaanxi, Shandong, Shanxi, Sichuan, Taiwan, SE Yunnan, Zhejiang [Japan, Korea].
The high-quality fibers are used to make cloth, paper, and ropes. The leaves are used as fodder and as traditional medicines to relieve internal fever.