276 CACAO 



pests. It is known that few plant troubles occur (whether 

 caused by insects or fungi) without a controlling agency 

 of some kind or another. In dealing with insect pests it is 

 often found that they are attacked by both animal and 

 vegetable parasites, and in some cases are directly con- 

 sumed by members of the animal kingdom. Where 

 attacked by parasites in sufficient numbers, the balance of 

 Nature is preserved, and the pest is under control naturally. 

 In cases where these are insufficient in number a study 

 of their habits may lead to measures for increasing their 

 numbers artificially, and thus attain the same end. In 

 such cases the control will evidently be cheaper than 

 spraying methods, but unless expert knowledge is available 

 the planter cannot know what, when, and how to spray 

 to advantage. Spraying under circumstances where there 

 is a natural control means the killing of friends as well as 

 foes and substituting a costly process in the place of the 

 cheap natural one, which will, in the end, tend to increase 

 the actual spread of the pest attacked. It is the same in 

 dealing with the vegetable or fungus parasites which attack 

 scale insects. In Trinidad there are fungi which attack 

 and destroy or keep in complete check one of the insects 

 attacking the orange. The humid climate of Trinidad 

 allows of the growth of this fungus, which is quite harmless 

 to the tree itself, but in drier climates probably would not 

 maintain its predominance. Therefore, a scale doing no 

 harm in Trinidad, owing to its being controlled by a fungus, 

 might do serious harm in places where a drier climate 

 prevails. Where such control exists, it is evident that 

 spraying is not required, but until the natural order of 

 things is fully recognised, it is probable that the unin- 

 structed will be induced to follow the fashion and spray 

 his trees ; a course which for him would be an expensive, 

 needless, and useless one in a great number of cases. 



Spraying is often recommended as a preventive. It 

 may readily be admitted that it is a preventive in some 

 cases to the entrance of fungi to the cacao pods. If a 

 spore rests upon the outside of a healthy pod it cannot 



