Black-hooked acacia (Senegalia laeta (R.Br. ex Benth.) Seigler & Ebinger, formerly known as Acacia laeta R.Br. ex Benth.), is an evergreen shrub or tree found in dry climates in Africa. Its leaves and pods provide valuable fodder for livestock. It yields an edible gum, though of lower value than that of Senegalia senegal.
Morphology
Senegalia laeta is a thorny shrub or small tree that reaches a height of 4-10 m. It has a rounded crown and a fissured, grey-green bark that seems to be black when seen from a distance (Orwa et al., 2009). Young branchlets are glabrous, grey-brown or rarely purplish bearing at each node a pair of hooked, purplish black or black, 3-5.5 mm long prickles. There is sometimes a third prickle or a leaf in its place. The leaves are bipinnate with 2-5 pairs of pinnae bearing 3-5 pairs of pinnate leaflets. The leaflets are 6-12 mm long, 2-7 (-10) mm wide, obovate-elliptic or oblong, glabrous or pubescent, clearly separated from each other and asymmetric. The inflorescence is a racemose spike, 3-8 cm long, that bears very fragrant, yellow, white or cream flowers. The stamens are conspicuous and yellow. Filaments are 5-7 mm long. The fruits are pale brown leathery, very flat, dehiscent pods, 3.5-8 cm long x 1.7-2.8 cm broad. The pods can be solitary or borne in tufts. Senegalia laeta yields only few pea-shaped seeds, 8-10 mm in diameter (FAO, 2017; Orwa et al., 2009; Bartha, 1970).
Uses
Senegalia laeta is a browse species whose leaves and pods are browsed by livestock. It produces an edible gum of pleasant flavour but of lesser quality than that of Senegalia senegal (FAO, 2017; Orwa et al., 2009; Baumer, 1983). The fragrant flowers make a valuable source of pollen and nectar for bees, beetles and butterflies. Black-hooked acacia provides excellent firewood and charcoal. Its wood is suited to make constructions, poles and fence-posts while its bark is used to make ropes and repair calabashes, or to produce tannins that are used to tan animal skins. Black-hooked acacias make live fences that can be browsed. This species has been used in afforestation programmes (FAO, 2017; Orwa et al., 2009).
