58 MANURING 



fying bacteria, and in addition aid in rendering mineral 

 elements already in the soil available for plant-food. 

 They encourage earth-worms, which bring up to the 

 surface a certaia amount of sub-soil. This becomes 

 weathered and converted into a state more suitable for 

 plant nourishment. 



It is unfortunately comparatively rare to find a suffi- 

 cient number of cattle maintained on a cocoa plantation 

 to supply an adequate quantity of manure for the whole 

 estate. It appears to the writer that considerable 

 advantage would be gained by increasing the number of 

 live stock on many cocoa estates, even if this necessitated 

 the allocation of a portion of the estate to the cultivation 

 of food crops for them. 



The importance attaching to the conservation of the 

 fertilising elements of cattle manure is often not suffi- 

 ciently appreciated. When exposed to atmospheric 

 influences valuable manurial elements are washed out 

 by heavy rains. The heating or fermentation caused 

 by the growth of bacteria rapidly converts its nitrogen 

 into ammonia, which escapes into the atmosphere unless 

 the manure be properly covered. If when cleaning out 

 the stock-yard it is not convenient to apply the manure 

 direct to the plantation, it should be stored under cover — 

 a thatched roof is well adapted for this purpose — and 

 soil should be thrown over the manure heap. Experi- 

 ments have shown that two-thirds of the fertilising 

 properties of farm-yard manure are lost by twelve months' 

 exposure to the atmosphere, including nearly all the 

 soluble nitrogen and 78 per cent, of the soluble mineral 

 ingredients. 



The liquid excrements of animals, being rich in potash 

 salts, etc . , are of considerable value for fertilising purposes, 

 and provision should be made to prevent their leaching 

 away from the stock-yard. Drains can be made at 

 comparatively little cost leading from the stock-yard to 

 the manure heap, over which the liquid should be 

 thrown. 



To this heap should also be added all decompos- 

 able refuse from the estate kitchens and labourers' 

 quarters. 



The following table shows the relative value of 

 various natural manures for fertilising purposes : 



