Indigofera hirsuta L.

Global description
 
Indigofera hirsuta is a subwoody plant, whose organs are abundantly covered with brown hairs, comprising of a long erect point and a short curved point. The leaves are alternate, with 5-7 elliptical leaflets. The inflorescences, 8-30 cm long, emerge from the base of the leaves and are carried by a long peduncle. They consist of many bright pink flowers (over 12).. The fruits are linear pods of 2 cm long, with few polygonal brown seeds. The fruits are folded at the bottom.
 
Cotyledons
 
The cotyledons are reniform and carried by a short petiole of 1 mm. The lamina is 7 to 8 mm long and 4 mm wide.
 
First leaves
 
The first leaves are alternate and simple. They are elliptical and long-stalked. The following leaves are trifoliate. At the base of the petiole, there are 2 filiform stipules of 2 mm long. Leaflets are elliptical and mucronate at the top. The stem, the petioles and the leaflets are covered with navicular hairs comprising of a long erect tip and short curved tip.
 
General habit
 
Erect plant, having the appearance of a small bush, with short shoots, woody at the base. Its height can reach 100 cm.
 
Underground system
 
The plant has a taproot system.
 
 
Stem
 
The stem is cylindrical, solid, thick and finely longitudinally striated. It is covered with navicular dense brown hairs, with a long erect point and a short curved point. The stem is often dark red.
 
Leaf
 
The leaves are alternate, compound and imparipinnate. They are carried by a long stalk, 10 to 20 mm. There are two filiform stipules of 10 to 15 mm long at the base of the petiole. A pair of stipels of 1 to 2 mm long is located under the insertion point of each pair of leaflets. The leaves include 5 to 7 very opposite leaflets, held by petiolules of 1 mm long. Leaflets are elliptic to obovate in shape. The terminal leaflet is usually larger than the lateral leaflet. The base is acute and the top is rounded, mucronate. They measure 15 to 50 mm long and 10 to 30 mm wide. Both sides are covered with strong pubescence consisting of navicular hairs erect including a long erect point and a short curved point. The margin is entire.
 
Inflorescence
 
The inflorescence consists of flowers arranged in the upper part of lateral axillary clusters. These clusters are compact, generally comprising of more than 12 flowers and are 8 to 30 cm long.
 
Flower
 
The flowers are supported by a pedicel of 2 mm and flowers one after another. The bract is long, linear, pubescent. The calyx consists of 5 linear and hairy tines, fused at the base. The corolla 10 mm long, is bright pink in colour. The outer face of the upper petal (standard) is hairy. The filaments of the 9 stamens are fused, whilst the 10th is free.
 
Fruit
 
The fruit is a nearly cylindrical pod, slightly angular. It is linear, 15 to 25 mm long and 3 mm wide. When ripe, the pods are folded downwards along the rachis. The top forms a short peak, extending the dorsal suture line. The dorsal surface is covered with a brown pubescence, especially in young fruit, the rest of the fruit is covered with a strong yellowish white pubescence. The pod contains 3 to 8 seeds and is dehiscent at maturity.
 
Seed
 
The seed is polygonal, 2 mm long and 1.5 mm wide. The dark brown seed coat is smooth, carved with small craters.

Worldwide distribution
 
Indigofera. hirsuta is very present throughout tropical and subtropical regions. It is particularly very common in West Africa.

https://www.gbif.org/fr/species/2972082