Included here is a zone mostly between 500-700 km wide extending from the Sudan-Ethiopian border westwards to the Atlantic coast of Senegal. The wider eastern border extends to the basin of Lake Victoria and includes the northwestern corner of Zaire, northern Uganda and small parts of Kenya.

In the savanna zones the woody species are often deciduous and typically include the endemic Anogeissus leiocarpus (Combretaceae) as the main species together with Albizia amara subsp sericocephala, Terminalia brownii and other endemic species such as Combretum glutinosum (Combretaceae), Isoberlinia doka (Fabaceae) and Khaya senegalensis (Meliaceae). In some of the dryer Anogeissus zones, such as in the Zamfara Forest Reserve west of Katsina in Nigeria, the principal tree species include a variety of additional endemic species among the dominant trees such as Albizia chevalieri (Fabaceae), Boswellia dalziellii (Burseraceae), Butyrospermum paradoxum (Sapotaceae), Lonchocarpus laxiflorus (Fabaceae), Piliostigma reticulatum (Fabaceae), Prosopis africana (Fabaceae), Sclerocarya birrea (Anacardiaceae) and Terminalia avicennioides (Combretaceae). The same is also true at the wetter end of the spectrum such as on the sandy plateau in the Yankari Game Reserve. Here endemic species such as Afzelia africana (Fabaceae), Combretum nigricans (Combretaceae) and Pericopsis laxiflora (Fabaceae) are likely to be encountered. A somewhat different composition occurs in the wooded grasslands at the edge of grassy floodplains (fadamas) where the characteristic trees include the endemic species Daniellia oliveri (Fabaceae) and Pseudocedrela kotschyi (Meliaceae). Also, in the extreme east of this zone, close to the frontier with Ethiopia there is a narrow strip of dark clay on sloping ground where Anogeissus leiocarpus shares dominance with Combretum hartmannianum. These savanna woodlands include the sporadic appearance of the endemic tree Sterculia setifera (Malvaceae).

References

Boughey, A. S. 1957. Ecological studies of tropical coastlines I. The Gold Coast, West Africa. Journal of Ecology, 45: 665-687.

Menaut, J. C. 1983. The Vegetation of the African Savannas. In: Ecosystems of the World 13 - Tropical Savannas. Ed. F. Bourliere. Elsevier Scientific Publishing Company.

Wickens, G. E. 1976. The flora of Jebel Marra (Sudan Republic). Royal Botanical Gardens Kew. HMSO.

White, F. 1983. The Vegetation of Africa. UNESCO.

Zohary, M. 1971. The Phytogeographical Foundations of the Middle East. In: Plant Life of South-West Asia. Eds. P. H. Davies, P. C. Harper and I. C. Hedge. The Botanical Society of Edinburgh.