THE NIGERIAN TIMBER TREES 335 



On the whole, however, this species is a little harder than 

 the other. 



This tree is somewhat slow-growing and stands less shade 

 than the Heudelotii. It is of the greatest value, with its aerial 

 roots, in protecting and increasing the height and stability 

 of the river banks at the edge of the dry forest zone. It is 

 one of the few trees that are not washed out of the banks in the 

 flood season, and even when they do fall over into the river 

 they remain attached to the bank and lessen the force of the 

 current. Natural regeneration is none too good. 



The timber has not been exported, nor has it been felled 

 locally for conversion into planks. Occasionally the natives 

 use the smaller trees for house-building. They also consider 

 the places in the rivers immediately near or overhung by one 

 of these trees as the best localities for fishing. 

 Bridelia micrantha. Yoruba Ironwood. Ira Odan, Asa Gidi 

 (Yoruba). 



It is found in the Ibadan and Abeokuta provinces of Nigeria. 



It is a small tree or shrub up to 8 feet high, with a large 

 alternate leaf. The bark tends to be fibrous and can be stripped 

 off in a similar way to the other Bridelias. 



The timber is very hard, moderately durable, and said to 

 be termite-proof. Its small size and somewhat crooked nature 

 hinders its more extensive use. 



It is occasionally of use for house-poles in temporary build- 

 ings, and makes good firewood, giving intense heat. The leaves 

 yield a rich humus and improve the soil. 



Native Use. — The bark is mixed with Hausa salts and then 

 drunk with lime and water as an aperient. 

 Bridelia Zenkeri, syn. atroviridis. Yoruba Ironwood. Asha, Asha 

 ragha (Yoruba) ; Oviaruza, Assivi, Ogangan (Benin). 



It is a comparatively common tree of the Abeokuta, Oyo, 

 Benin and Owerri provinces of Nigeria. The roughly fissured 

 bark, scaling off in criss-cross fashion, in papery or fibrous 

 layers, is most typical of the tree. The bole is short, seldom 

 reaching a greater length than 15 feet. It is usually forked about 

 this height and then spreads out, rather reminiscently of the 

 elm. It yields the hardest wood of all the African trees, except 

 perhaps Okuta (the stone). 



It is occasionally used for house-building by the natives. 

 Bridelia stenocarpa. Benin Ironwood. Arasha, Asha, Aroro 

 Ashasha (Ondo), Aiveygbo (Eg.) (Yoruba) ; Assivi (Benin). 



This tree is found in the Benin and Calabar provinces of 

 Nigeria, where it is somewhat prevalent, but found always 

 singly in the forest. In habit it is not at all unlike the wych 



