OTHER FIELD CROPS 161 



tion, the plants being put in at about 4-6 inches apart. 

 The whole cultivation is done during the dry season, 

 and the beds are irrigated by means of channels supplied 

 with water raised from streams or wells, in the north by 

 shadufs, or in the Nupe country by people conveying 

 the water in calabashes. 



The market price varies greatly in different districts, 

 and is immediately influenced by any reduced supply. 

 There is said to be a very good demand for the large 

 onions in the Southern Nigerian markets, and there 

 should be no difficulty in getting them to Lagos, as 

 they have been brought from Kano to London in good 

 condition. 



Minor Crops. Okra (Hibiscus esculentus), " Kubiewa," 

 a species of Solanum resembling a small tomato called 

 "Yalo," the sorrel Hibiscus (H. Sabdariffa) called 

 " Yakwa," a pumpkin called " Kubiwa," and the auber- 

 gine (Solanum melongena), are grown upon a small scale, 

 and chiefly in the vicinity of houses. 



OTHER FIELD CROPS. Dye Plants. Indigo is the 

 chief dye used in the country, and is prepared in the 

 northern provinces from a species of Indigofera, which 

 has not been accurately determined. 



In Ilorin and Kabba the plant used is Lonchocarpus 

 cyanescens, and the wild trees of this species may be 

 seen preserved in the cultivated fields. 



Camwood, a name applied to the red wood obtained 

 from several species of Pterocarpus and from Baphia 

 nitida, in different parts of West Africa, is obtained 

 chiefly from P. erinaceus in Northern Nigeria, and is 

 used by the natives for staining the skin. It is pre- 

 served in the fields cleared for grain cultivation. 



Henna is obtained from Lawsonia inermis, which is 

 regularly planted as a sole crop in the northern provinces 

 and Kontagora. The use of it is generally to replace 

 camwood as a red dye where that tree is scarce. 



Tobacco. The cultivation of tobacco (Nicotiana taba- 

 cum) is carried on in almost every part of the country, 

 but for native use is generally made into snuff or into 

 ropes, plaits, and targets, for sale in those places where 

 it is smoked. (Cf. Bull. Imp. Inst., vol. xv. [1917], p. 32.) 



The crop is usually grown in the river valleys, and is 

 irrigated carefully. Manure in the form of house sweep- 



