THE CULTIVATION OF COCOA 165 



though in countries where labour is expensive it may be 

 a question whether this tillage will pay or not. 



Another kind of tillage superficial hoeing has a 

 different object, namely, to prevent the soil from evapora- 

 ting too much and becoming too dry. In countries 

 where some part of the year is very dry, and where 

 cocoa often suffers from drought during this period, a 

 superficial hoeing at the beginning of the dry season 

 is useful,, and will be specially advantageous if for 

 any reason the layer of mulch on the soil is only poor. 

 Accordingly, this method is specially valuable in fields 

 where cocoa is cultivated without shade. The effect of 

 superficial hoeing consists in covering the soil with a 

 layer of loose earth, through which the underlying soil 

 cannot evaporate its water so easily ; for the very small 

 canals, the so-called capillary canals, which run like 

 continuous, more or less vertical tubes through a compact 

 soil, are covered by the loose earth on the top, instead 

 of running up to the surface. In this way evaporation 

 of the soil is much reduced, and in addition the super- 

 ficial hoeing kills the weeds, especially those which live 

 on a root-stock, and which therefore are not killed by 

 the ordinary weeding. 



Manuring. Many planters are of the opinion 

 expressed in Hart's well-known book : "a tree in 

 good health needs no manure," * and if yearly crops 

 are obtained which are regarded as satisfactory, they 

 often do not trouble themselves with the question 

 whether the yield could still be increased by manuring. 

 On many plantations, therefore, manuring, like tillage, 

 is not regarded as one of the necessary operations. 



But though there may be countries where the soil 

 is so rich that even after cocoa has been grown on 

 it for a great number of years no kind of manuring 

 would increase the yield, it is more than probable 

 that systematic experiments would show that in most 

 countries manuring, whether with farmyard manure, 

 mulch, or with some kind of chemical manure, would 



1 Hart, Cacao (1911), p. 52. 



