Prota 7(1): Timbers/Bois d’œuvre 1
Oliv., Fl. trop. Afr. 2: 183 (1871).
Papilionaceae (Leguminosae - Papilionoideae, Fabaceae)
Origin and geographic distribution
Erythrina excelsa is widespread from Côte d’Ivoire and Mali east to Kenya and south to Zambia.
The wood is popular in Uganda for making drums, and is also used for stools, shields, mortars and carving for the tourist industry. It is used as fuelwood and for making charcoal. The bark sap is administered as an antidote for snakebites. Erythrina excelsa is locally planted as an ornamental and roadside tree.
The wood is yellow-white, lightweight, soft and easy to work. Isoflavonoids have been isolated from the bark.
Deciduous medium-sized tree up to 30(–45) m tall; bole straight, branchless for up to 20 m, up to 80(–250) cm in diameter, armed with woody, conical spines, sometimes with steep buttresses up to 7 m high; bark surface smooth, pale, inner bark yellow; twigs armed with prickles. Leaves alternate, 3-foliolate; stipules triangular, up to 4 mm long, persistent; petiole 4–21 cm long, often prickly, rachis 2–8.5 cm long, with large glands at base of petiolules, stipels 2–3.5 mm long, petiolules 6–12 mm long; leaflets elliptical to ovate or oblong-elliptical, 7–23.5 cm × 3.5–16.5 cm, rounded to slightly cordate at base, acute or shortly acuminate at apex, initially hairy especially below but glabrescent, pinnately veined with c. 9 lateral veins. Inflorescence an axillary or terminal, erect, compact false raceme 10–35 cm long; bracts up to 1 cm long, early deciduous. Flowers bisexual, papilionaceous; pedicel 4–8 mm long; calyx spathe-like, glabrous or slightly hairy, split at one side, tube 1–2 cm long, limb 1–3 cm long, at apex with 2 acute teeth up to 8 mm long; corolla orange-red to scarlet red or coral-red, standard 2–4 cm × 1.5–2.5 cm, reflexing with age, wings 8–11 mm long, keel 6–10 mm long; stamens 10, fused to c. halfway but 1 almost free; ovary superior, narrowly cylindrical-oblong, 1-celled, style glabrous. Fruit a linear-oblong spirally twisted pod up to 20 cm long, markedly constricted between the seeds, densely brown hairy, opening by 2 valves, up to 10-seeded. Seeds 11–16 mm long, orange-red, with whitish scar.
Trees of Erythrina excelsa grow very fast. They usually flower when they are quite leafless. The flowers contain much nectar and are visited by sunbirds and bees.
Erythrina comprises approximately 120 species: about 30 in continental Africa, 6 in Madagascar, 70 in tropical America and 12 in tropical Asia and Australia.
Erythrina excelsa is usually found in riverine and swamp forest, up to 1500 m altitude.
Erythrina excelsa is propagated by seed, but seeds are liable to insect attack, even while still on the tree. It can also be propagated by cuttings and by collecting wildlings. Cuttings are used for planting as living fence material. Planted trees can be managed by pollarding.
Genetic resources and breeding
Erythrina excelsa is widespread, but seems to be uncommon or even rare in many parts of its distribution area. In some regions it is reported to be common, e.g. in the forest belt near Lake Victoria in Uganda. In regions in Uganda where the wood is commonly used in the drum-making industry, the number of mature trees has decreased significantly.
As is the case in many Erythrina species, Erythrina excelsa deserves more attention in tropical Africa as an indigenous multipurpose tree, combining ornamental, auxiliary and timber values. Planting should be encouraged, especially in regions with heavy exploitation of natural populations for making drums.
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Correct citation of this article:
Lemmens, R.H.M.J., 2008. Erythrina excelsa Baker. In: Louppe, D., Oteng-Amoako, A.A. & Brink, M. (Editors). Prota 7(1): Timbers/Bois d’œuvre 1. [CD-Rom]. PROTA, Wageningen, Netherlands.