37. Indigofera hirsuta Linnaeus, Sp. Pl. 2: 751. 1753.
硬毛木蓝 ying mao mu lan
Shrubs or shrublets, erect, 30-100 cm tall. Stems rufous, with spreading rust-colored basifixed extremely asymmetrically 2-branched trichomes looking like simple trichomes. Stipules narrowly triangular, 1-1.2 cm. Leaves 2.5-10 cm, 5-9-foliolate; petiole and rachis adaxially grooved, with spreading rust-colored basifixed trichomes; petioles 0.8-1.2 cm; stipels 1-2 mm; petiolules 1.5-2 mm; leaflet blades opposite, elliptic to obovate, 1.5-3.5 × 0.7-2 cm, both surfaces with dense spreading gray basifixed trichomes, midvein abaxially prominent, secondary veins 4-6 on each side of midvein, base cuneate, apex rounded and with a ca. 0.2 mm mucro. Racemes 10-20 cm, densely flowered; bracts linear-triangular, ca. 4 mm, caducous. Pedicel ca. 2 mm, deflexed after flowering. Calyx 4-6 mm, with spreading gray basifixed trichomes; tube ca. 1 mm; teeth setaceous, 3-5 × as long as tube. Corolla red; standard with white blotches at base, obovate-elliptic, 4-5 × 3-4 mm, outside hairy; wings 4-5 × 1.2-1.5 mm, glabrous, apical margin hairy; keel white with a red tip, 4-5 × 1.2-2.5 mm, glabrous, apical margin hairy, spur ca. 0.7 mm. Stamens 3-4.5 mm; anthers ovoid. Ovary hairy, with 6-9 ovules. Legume cylindric, straight, round in cross section, 1.5-2 cm × 2-2.5 mm, with spreading trichomes; endocarp black blotched. Seeds 6-9 per legume, brown, cubic. Fl. Jul-Sep, fr. Oct-Dec. 2n = 16.
Open slopes, trailsides, grasslands near rivers, sandy ground near seashores; below 100 m. Fujian, Guangdong, Guangxi, Hainan, Taiwan, SE Yunnan, Zhejiang [Bangladesh, Cambodia, India, Indonesia, Laos, Malaysia, Myanmar, Philippines, Sri Lanka, Thailand, Vietnam; Africa, N Australia, Pacific islands].