1. Apocynum venetum Linnaeus, Sp. Pl. 1: 213. 1753.
罗布麻 luo bu ma
Apocynum lancifolium Russanov; A. venetum var. ellipticifolium Beguinot & Belanger; A. venetum var. microphyllum Beguinot & Belanger; Trachomitum lancifolium (Russanov) Pobedimova; T. venetum (Linnaeus) Woodson; T. venetum var. ellipticifolium (Beguinot & Belanger) Woodson; T. venetum var. microphyllum (Beguinot & Belanger) Woodson.
Stems to 4 m tall, glabrous except for inflorescences; branches and branchlets whitish gray, terete, finely striate. Leaves usually opposite; petiole 3-6 mm; leaf blade narrowly elliptic to narrowly ovate, 1-8 X 0.5-2.2 cm, base rounded or cuneate, margin denticulate, apex acute or obtuse, mucronate. Sepals narrowly elliptic or narrowly ovate, ca. 1.5 mm. Corolla purplish red or pink; tube campanulate, 6-8 mm, granulose; lobes 3-4 mm. Disc fleshy, 5-lobed; lobes rounded, base adnate to ovary. Follicles slender, 8-20 cm X 2-3 mm. Seeds ovoid or ellipsoid, 2-3 mm, coma 1.5-2.5 cm. Fl. Apr-Sep, fr. Jul-Dec. 2n = 22.
Salt-barren zone, desert margins, alluvial flats, riversides. Gansu, Hebei, Henan, Jiangsu, Liaoning, Nei Mongol, Qinghai, Shaanxi, Shandong, Shanxi, Xinjiang, Xizang [India, Japan, Mongolia, Pakistan, Russia; SW Asia, Europe]
The strong bast fibers obtained from the inner bark are used in making cloth, strings, sails, fishing nests, and high-quality paper. The leaves yield up to 5% gum, which is used for making rubber, and a medicine used as a sedative and to treat hypertension. The species has fragrant flowers and is grown as a honey plant.