Albizia brownei (Walp.) Oliver

Albizia zygia is a deciduous tree 9-30 m tall with a spreading crown and a graceful architectural form. Bole tall and clear, 240 cm in diameter. Bark grey and smooth. Young branchlets densely to very sparsely clothed with minute crisped puberulence, usually soon disappearing but sometimes persistent. Leaves pinnate, pinnae in 2-3 pairs and broadening towards the apex, obliquely rhombic or obovate with the distal pair largest, apex obtuse, 29-72 by 16-43 mm, leaves are glabrous or nearly so. Flowers subsessile; pedicels and calyx puberulous, white or pink; staminal tube exserted for 10-18 mm beyond corolla. Fruit pod oblong, flat or somewhat transversely plicate, reddish-brown in colour, 10-18 cm by 2-4 cm glabrous or nearly so. The seeds of A. zygia are smaller (7.5-10 mm long and 6.5 to 8.5 mm wide) and flatter than either of the other Albizia, but have the characteristic round shape, with a slightly swollen center. The genus was named after Filippo del Albizzi, a Florentine nobleman who in 1749 introduced A. julibrissin into cultivation.

A hermaphroditic species flowering in January, February, March, August, and September. Fruits ripen in January, February, March, April, November, and December. This tree hybridizes with A. gummifera.

Prefers well drained loamy or clayey soils. It has been found to be tolerant to soil acidity and water stress.

A light demanding pioneer species, it is rarely found in closed canopy forests dominated by Chlorophora regia and Ficus macrosperma. Common in lowland coastal rain-forests, riverine forest and in woodland. This tree is indigenous to tropical Africa and has a wide distribution, from Senegal in west Africa to eastern Africa.

A. zygia is an African tree growing wild and is used to provide shade for cacao.

Vegetative propagation using leafed cuttings enriched with Indole-3-butyric acid, show significantly higher rooting percentage, root length, and root numbers. Natural seedborne regeneration is popular but seeds may require a pretreatment. Wild seedlings can be transplanted to favourable sites or protected in situ.

A rapidly growing tree, a two year old tree can be 3 m tall. Has little management needs, however pollarding and coppicing are recommended for form improvement and propagation.

Members of one of the insect genus Entedon eat A. zygia seeds. Some seedborne pathogenic fungi are reported in this species.

A pretreatment of c. 100 seeds with 30 ml 98% sulphuric acid for five minutes followed by thorough washing in free flowing tap water significantly improves germination by up to (86%).

Erosion control: With a fairly deep rooting system A. zygia has great potential to protect vulnerable soils. Shade or shelter: Provides shade for cacao trees in plantations. Reclamation: Has a high potential for ameliorating degraded cocoa soils. The species also exhibits characteristics of drought avoidance. Nitrogen fixing: A. zygia is confirmed as nodulating, Rhizobium-type root nodules were found on roots of mature specimens of A. zygia. Greenhouse and field experiments indicate the tree is also capable of symbiotic nitrogen fixation with Bradyrhizobium and forming vesicular arbiscular mycorrhiza. Soil improver: Provides mulch leaf litter and improves the pH in acidic soils. Ornamental: As an ornamental this showy tree can grace avenues and recreation sites. Boundary or barrier or support: Though termite vulnerable, the wood can be used for temporary structures or fencing. Intercropping: As an agroforestry tree, it is still untested but looks promising. In Ghana the tree is one of the most favoured cacao shade trees. Other services Provides shelter, shade and serves as a windbreak.

Food: The young leaves are cooked and consumed as a vegetable, especially in soups. Analysis of the seeds reveals a low crude protein content. Amino acids such as lysine, sulfur amino acids and threonine are limiting, indicating the limited nutritional value of A. zygia seeds. Fodder: The shoots and leaf are eaten by livestock. Apiculture: The nectariferous flowers attract bees. Fuel: Provides considerable amounts of charcoal in Ghana and fuelwood in other localities. Timber: Produces a class three timber with the trade name “Okuro”, this is a quality timber with a pale brown heartwood fairly easy to work, durable but not termite proof. Used in construction, making handles of farm implements, household utensils and furniture. A. zygia is a preferred species for wood carving in the Democratic Republic of Congo. Gum or resin: A viscous gum from A. zygia can be used as a stabilizer in ice-cream. Tannin or dyestuff: Bark has tannins. Medicine: Molluscicidal activity shown by leaf extracts of A. zygia.