62. Indigofera howellii Craib & W. W. Smith, Notes Roy. Bot. Gard. Edinburgh. 12: 207. 1920.
长序木蓝 chang xu mu lan
Indigofera deginensis Sanjappa; I. emarginata Y. Y. Fang & C. Z. Zheng.
Shrubs, to 3 m tall. Stems brown, terete, with yellowish lenticels, with appressed medifixed symmetrically 2-branched trichomes. Stipules narrowly lanceolate, 2-3 mm, with appressed brown trichomes. Leaves 9-11 cm, (7 or)9-17(-23)-foliolate; petiole and rachis with sparse appressed white and some brown medifixed trichomes; petiole (0.5-)1-3(-4) cm; rachis terete, adaxially narrowly grooved; stipels minute; petiolules ca. 1 mm, with appressed medifixed trichomes; leaflet blades opposite, elliptic, 0.8-3(-3.5) × 0.3-1.5(-2) cm, thinly papery, both surfaces with appressed white medifixed trichomes, midvein abaxially prominent and adaxially impressed, secondary veins 4 or 5 on each side of midvein and adaxially obvious, base broadly cuneate, apex rounded to truncate and with a ca. 1 mm mucro. Racemes 10-20 cm, densely flowered; peduncle and rachis hairy; peduncle 1-2 cm; bracts ovate to ovate-lanceolate, 2-3 mm, caducous, abaxially with brown trichomes. Pedicel 2-3 mm. Calyx cup-shaped, (2-)3-4 mm, outside hairy; tube ca. 2 mm; teeth triangular to lanceolate, ca. 1-2 × as long as tube. Corolla purple; standard obovate to obovate-elliptic, 8-10.5 × 5-6 mm, outside with dense appressed white trichomes, base shortly clawed, apex obtuse; wings 8-10 × ca. 2.5 mm; keel 8-10.5 mm, outside apically hairy. Stamens (6.5-)7-8 mm; anthers ovoid, base with a few trichomes. Ovary glabrous. Fl. May-Sep, fr. unknown.
● Scrub, sparse forests on hill slopes; 800-3500 m. SW Sichuan, Xizang, W Yunnan.
Most material cultivated in England as Indigofera potaninii (here treated as a synonym of I. szechuensis) belongs instead to I. howellii.