126 NIGERIA NORTHERN PROVINCES 



from which the loose soil has been removed increase the 

 apparent height by the extent of their depth, and give 

 the appearance of a good form of tillage having been 

 practised. This is, however, seldom the case, as, except 

 where irrigated crops are being treated, the ground is 

 left untilled beneath the thrown-up soil. To compensate 

 for the shallow state of the cultivation, manure is applied 

 in large quantity, all animal refuse and ashes being 

 carefully preserved, and often conveyed for long distances 

 to the fields by men or donkeys. 



The above conditions apparently apply only to the 

 Haussa race, the pagan Gwaris and Bassas resorting to 

 a much deeper form of cultivation and employing no 

 manure. The Nupes and Yorubas do not know the use 

 of manure for any crops except onions and tobacco, for 

 both of which wood ashes are the chief substance 

 applied. 



The crops of the country may be roughly divided into 

 rainfall, irrigated, and swamp kinds. The first are sown 

 at the commencement of the wet season, and are greatly 

 affected by the distribution of the rain, but include the 

 most important sources of food. These are Guinea corn, 

 millet, maize, groundnuts, cassava, sweet potatoes, etc. 

 An inadequate or irregular rainy season often causes 

 famine conditions. The irrigated crops are yams, Colo- 

 casia, onions, tobacco, peppers, rama-fibre, and wheat, 

 the last being almost confined to the country north 

 of the llth degree. Cassava and sugar-cane are also 

 frequently irrigated in the drier districts to the north. 

 Irrigation is performed in the northern localities by 

 means of the shaduf. The swamp crops are rice, 

 Colocasia, and sugar-cane. The first is grown upon a 

 flat-dug surface, the second upon high ridges made of 

 swamp mud, and the third on low ridges bordering the 

 rice fields. The villages north of Kano are often entirely 

 built of the stalks of Guinea corn, and Fig. 31 represents 

 a principal hut within such a structure. The fencing of 

 the fields in this locality is generally made of the same 

 material, but in the vicinity of Kano itself, Euphorbia 

 or thorn hedges are more common. 



Near Rogo, fences and hedges are usually dispensed 

 with, paths forming the boundaries between fields. 



The following table of value of exports shows the pro- 



