nilotica ssp. (L.) Willd. ex Del.
tomentosa (Benth.) Brenan
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InterestAn important source of firewood and good quality charcoal in the Sahelian regions. Similar to the other subspecies, its wood is dark red, hard and durable. It is termite and water resistent. Recorded uses include turnery, pit props, sleepers, boat building, wagons and construction timbers to name but a few. De-seeded pods contain up to 50% tannin. Occasionally planted as a shade tree in the Sahel. In Burkina Faso has similar uses to those of subsp. adstringens (Wickens et al. 1995).
Other NotesSpecies characteristics: Very widespread species in Africa and also streaching to the Indian subcontinent and Shri Lanka, it is divided into nine subspecies. Single stemmed, deciduous or evergreen tree, usually 2.5-15 m tall, but reaching 25 m or more in the riverine subspecies, with a flattened spreading or rounded crown. Root system deep and extensive in dry sites, the taproot developing first and then the laterals, which become compact and massive, but in flooded sites the root system is largely lateral. Distinguished from most African Acacia species in possessing long straight paired thorns at the leaf axil which are characteristically deflexed. Acacia nilotica in Africa exhibits two very distinct ecological preferences: the subspecies subalata, leiocarpa and adstringens occur in wooded grassland, savanna and dry scrub forests on deep sandy loamy soils, and also on lateritic and calcareous sites. Subsp. kraussiana also prefers dry grasslands and savannas, especially on compacted sandy loam, shallow granite or clay soils along drainage lines and rivers, but away from flooding. On the other hand, subspecies nilotica and tomentosa are restricted to riverine habitats and seasonally flooded areas on clay alluvial soils. In the Indian subcontinent, subsp. indica forms low altitude dry forests usually on alluvium soils subject to flooding or black cotton soils. Now widely planted on farms throughout the plains, it will also grow on saline, alkaline, and on soils with calcareous pans. Common names: Senegal: Gonakie (Wolof). Distribution: Burkina Faso (Volta Noire); Egypt (Upper Egypt); Ethiopia (Shewa, Awash valley); Mali (Gao); Mauritania (Tagant, Brakna); Niger (Dosso); Nigeria (Northern); Senegal (Saint Louis); Sudan (Khartoum, Kordofan); Cape Verde (Ilha de Santiago, Ilha de Santo Antao, Ilha de Maio, Ilha de Fogo, Ilha da Boa Vista). Altitude range: 20-760m