8. Scirpus rosthornii Diels, Bot. Jahrb. Syst. 29: 228. 1900.
百球藨草 bai qiu biao cao
Rhizomes short. Culms 70-100 cm tall, stout, 3-angled, stiff, nodose. Leaves overtopping inflorescence; sheath 3-12 cm, with transverse veins; leaf blade 0.6-1.5 cm wide, ± stiff, abaxial midvein and margin scabrous. Involucral bracts 3-5, leaflike, usually overtopping inflorescence. Inflorescence a large terminal decompound anthela; rays 6 or 7, to 12 cm, stout, scabrous. Spikelets sessile, in headlike clusters of 4-15, ovoid to ellipsoid, 2-3 × ca. 1.5 mm, many flowered, apex subrounded. Glumes straw-colored to brown but later becoming blackish brown, broadly ovate, ca. 1 mm, with 3 green veins, apex obtuse. Perianth bristles 2 or 3, longer than nutlet, erect, apical half antrorsely scabrous. Stigmas 2. Nutlet yellow, ellipsoid to subspherical, 0.6-0.7 mm, biconvex. Fl. and fr. May-Sep.
Forests, forest margins, slopes, trail margins, wet places, swamps; 300-2600 m. Anhui, Chongqing, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Henan, Hubei, Hunan, Jiangxi, Shaanxi, Shandong, Sichuan, Xizang, Yunnan, Zhejiang [Japan, Nepal].