野青树 ye qing shu

Shrubs or shrublets, erect, 0.8-1.5 m tall. Stems grayish green, with appressed medifixed symmetrically 2-branched tri­chomes. Stipules narrowly triangular, ca. 4 mm. Leaves 5-10 cm, 11-15(-19)-foliolate; petiole and rachis adaxially grooved, with appressed medifixed trichomes; petiole ca. 1.5 cm; leaflet blades oblong to oblanceolate, 1-4 × 0.5-1.5 cm, abaxially pale green and with appressed medifixed trichomes, adaxially green and with dense appressed medifixed trichomes or glabrescent, base broadly cuneate to rounded, apex acute to rarely rounded. Racemes 2-3 cm, densely flowered; peduncle very short or ab­sent; bracts linear, ca. 2 mm, caducous, abaxially with ap­pressed medifixed trichomes. Pedicel reflexed in fruit. Calyx ca. 1.5 mm, outside hairy; teeth broadly triangular, as long as tube. Corolla red; standard obovate, 4-5 mm, outside with dense brown trichomes; keel as long as wings, hairy. Stamens 3-4 mm; anthers globose, glabrous, apex mucronate. Ovary densely hairy. Legume deflexed and upwardly falcate, 1-1.5 cm, hairy; endocarp blotched. Seeds 6-8, brown, shortly cylin­dric, both ends truncate. Fl. Mar-May, fr. Jun-Oct. 2n = 16, 32.

Cultivated or naturalized in Fujian, Guangdong, Guangxi, Jiangsu, Taiwan, Yunnan, and Zhejiang [native to tropical America; widely cultivated in tropical and subtropical Asia].

Indigofera suffruticosa is cultivated as an alternative to I. tinctoria for the production of the dye indigo.