Indigofera suffruticosa
Gard. Dict. ed. 8, Indigofera no. 2. 1768.
Herbs, perennial, strigose, hairs appressed, grayish silvery. Stems erect or ascending, many stems from ground, much-branched distally, stems angled, 5–20 dm. Leaves 6–11 cm; stipules narrowly triangular, attenuate, 5–6 mm; petiole 10–20 mm; stipels 0.5–1.5 mm; petiolules 0.5–1.5 mm; leaflets 9–17, opposite, blades elliptic or oblanceolate, 15–20(–40) × 5–10(–15) mm, base cuneate, apex acute, mucronate, surfaces strigose, abaxially sometimes glabrate. Peduncles 0.5 cm. Racemes 20–30+-flowered, dense, 3.5–5.5 cm. Pedicels 1 mm. Flowers 5–6 mm; calyx 1.5–2 mm, lobes deltate to lanceolate; corolla greenish yellow, orange, or purple-pink. Legumes dark brown, reflexed, cylindric, strongly curved, 15–20 mm, leathery, base not bulbous or reddish, strigose to glabrate. Seeds 4–6, reddish brown, cuboid. 2n = 16, 32.
Phenology: Flowering year-round.
Habitat: Dry, sandy, open woodlands, along streams, abandoned fields, ruderal or agricultural areas.
Elevation: 0–300 m.
Distribution
Introduced; Fla., Ga., La., Miss., N.C., S.C., Tex., Central America, South America (Argentina, Brazil, Paraguay, Uruguay), introduced also in Asia, Africa, Pacific Islands, Australia.
Discussion
Indigofera suffruticosa is probably native to the New World tropics and subtropics. In the New World, it became a major source of blue dye. It was spread through cultivation to other regions of the world (P. C. Standley and J. A. Steyermark 1946).
Selected References
None.