62 CACAO 



The " mortel " or shade tree, Madre de cacao, or Ery- 

 thrina, of several species, is known to produce flowers 

 showing a high nitrogen content. Analyses of flowers 

 of these trees, published locally in 1901 and 1902, showed a 

 difference of 40 per cent, in the nitrogen content. In the 

 latter year the ascertained percentage of ten samples was 

 3-35 per cent., while in 1901 the report showed a return 

 40 per cent, higher. 



Flowers of the English elm have been found to contain 

 3' 54 per cent, of nitrogen, while the flowers of Gliricidia, 

 the tree used as shade in Nicaragua, gave 3' 30 per cent, 

 of nitrogen. 



As regards manuring in general, it is necessary for the 

 cacao planter to ascertain for himself the kind or class of 

 manure he can use with greatest success on the various 

 portions of his estate. It by no means follows that a 

 manure suited for one portion of a plantation would be 

 suitable for another field ; nor can the manures used 

 successfully by a neighbour be relied on as suitable for 

 other fields until proved so by actual trial and experiment 

 of sufficient duration, and the chemist has to prove by 

 experiment as well as the planter. The method of appli- 

 cation of manure is another question to be considered. 

 Sometimes manure is best applied in small quantities at 

 intervals, at other times it may be applied in larger 

 quantities with better effect. Some manures may be 

 mixed with others, and some may on no account be mixed. 

 In mixing manures before applying them to the land, 

 chemical changes can take place, so that a valuable 

 ingredient may be lost by a part of it flying off as gas, 

 as for example the mixing of lime with such as actually 

 contain nitrogen, stable manure, guano, or ammonimn 

 sulphate, &c., when the most valuable ingredient, the 

 nitrogen, is lost in the form of ammonia. Sometimes an 

 easily soluble manure changes into one soluble with diffi- 

 culty, and so loses in value, as for example the influence 

 of lime on easily soluble phosphates. Secondly, mechanical 

 changes can be caused by mixing two or more manures, 



