5. Senna hirsuta (Linnaeus) H. S. Irwin & Barneby, Phytologia. 44: 499. 1979.
毛荚决明 mao jia jue ming
Cassia hirsuta Linnaeus, Sp. Pl. 1: 378. 1753.
Herbs or shrubs, 0.6-2.5 m tall. Young branches, petioles, and rachises of leaves densely yellowish brown villous. Leaves 10-20 cm; petiole 3-6 cm, with a sessile, blackish brown, ovoid-oblong gland near insertion; rachis 7-10 cm, without glands; leaflets 3-7 pairs, ovate-oblong or oblong-lanceolate, 3-9 × 1.5-3.5 cm, papery, both surfaces villous, base subrounded, apex acuminate. Racemes axillary or several in axils of apical leaves forming a leafy panicle; peduncles and pedicels villous; bracts early caducous, subulate, hairy. Sepals 5, unequal in size, densely villous, 2 outer small, ovate to obovate, ca. 5 mm, 3 inner puberulent, similar but larger, 7-8 mm. Petals yellow, obovate, 1.4-1.8 cm, glabrous. Stamens 10, 6 or 7 of them fertile, unequal in length, anthers opening by apical pores, staminodes 3 or 4. Ovary hirsute, subsessile; style short, glabrous; stigma small. Legume long, slender, flat, 10-20 × ca. 0.5 cm, densely hirsute on surfaces of valves. Seeds numerous, flat, obovoid, 3-4 mm. 2n = 14, 28.
Cultivated in Guangdong, Yunnan [native to tropical America; introduced in the tropics elsewhere].