198 WEST AFRICAN FORESTS AND FORESTRY 



possessed by grasses and low, scattered shrubs, often thorny. Never- 

 theless, good pastures are often to be found, frequented by the Fulani 

 in the comparatively short rainy season, and only at some points 

 towards the French boundary do the conditions approach those described 

 by Barth in the latitude of Zinder and Timbuctoo. For example, part 

 of North Bornu, with a rainfall sometimes not exceeding 10 inches, may 

 exhibit features entitling it to rank with the upper region of Chevalier's 

 " Zone Sahelienne." A typical association in these scrub regions is 

 familiar to the Hausas in three of the plants mentioned below, viz. 

 the Sabarra, Guiera Senegalensis, the Magariya, Zizyphus jnjuba, and 

 the Dashi, Balsamodendron Africanum. Sokoto, with an average 

 rainfall of 25 or more inches, still possesses thinly treed savannahs 

 and bush -lands, with a vegetation composed of grasses, small sedges, 

 low shrubs and the commoner leguminous and other weeds. 



Nor does the transition occur evenly across the whole region. In 

 the eastern part between Kano and North Bornu the Acacia type 

 prevails, and whole areas may occur occupied largely by Acacia Seyal, 

 with yellow or rusty ochrey bark. On the western side Acacias, though 

 present, do not appear to prevail, and between Kano and Sokoto there 

 exists a stretch of broad-leaved forest in which most of the species 

 found in Central Hausaland reappear, but after all these differences 

 may be found to hold only over limited areas. 



The wide and well populated circle around large northern towns, 

 highly cultivated and more or less stripped of trees to supply fuel 

 does not quite display the natural conditions of the bush, where 

 uncontrolled fires prevent natural regeneration of forest on cleared 

 land, and where open grassy formations with stunted vegetation 

 tend to encroach on the higher types of tree savannah. 



The species more characteristic of the northern drier belt within 

 the Soudan Zone — if an arbitrary limit is allowed we may place it 

 about 12° North latitude — may now be briefly indicated, though it 

 will be understood that many of them are already present farther 

 south. 



Capparidace^ : most of the species of Capparis, Boscia and Mcerua 

 existing farther south here prevail ; the low shrub Boscia Senegalensis 

 is common, while Cadaba farinosa is a characteristic shrub. 



SiMARUBE^ : the Aduwa, Balanites jEgyptiaca, is a typical species 

 of this region. 



BuRSERACE>E : the Dashi, Balsamodendron Africanum, a shrub 

 yielding African Myrrh, is familiar, with its congener B. pedunculatum. 



Rhamnace^ : the Kurna, Zizyphus Spina-Christi, usually planted 

 in towns, the Magariya, Z. jujuba, and the Magariyar kura, Z. 

 mucronata, the last two being very characteristic of the open savannah. 



Anacardiace^ : the Danya, Spondias sp., a fair-sized tree with 

 yellow, plum-like fruit having a leathery rind, is abundant. 



