CHAPTER X. 



Diseases, &c. Insect Pests, Fungi, Vegetable Parssites, 

 Epiphytes, and other enemies. 



ORTUNATELY for the cultivator the serious- 

 diseases which at present attack the Cacao tree* 

 in the West Indies, are few, except the plant i* 

 placed in a totally unsuitable position. Perhaps 

 the mo.st common disease affecting the tree, is one 

 which is known under the name of Canker. This 

 cause the stem and branches to dry in certain 



spots and along certain lines and generally results in the death 



of the tree. 



The cause of this disease is not yet fully clear, but a fungus 

 of the parasitic type has been found on Cacao pods, the allies of 

 which are known to cause canker of the bark on other trees. 

 This has been named Seclria bainn, Massee, and will be 

 discussed later. Generally speaking, however, ^hen trees are 

 planted in well drained ground, little or no disease is found ; but 

 where a poor surface soil badly drained exists, canker will 

 appear (Canker of the bark has aho been found to be due to a 

 Xectria December, 1899.) 



There is another disease found in Trinidad, Surinam, 

 Grenada and other places, which attacks the pods in damp 

 weather and causes them to rot and turn black, hence sometimes 

 called ' black rut" or " black Cacao." This is due to a parasitic 

 fungus recently studied and forwarded to Kew by the Author, 

 where it was determined us rhytophihora omnivora, a fungus 

 akin to that (I'hytophthora infestans} which destroys the 

 Potato (Sulanum ttiuerosum.) 



The following extract from De Verteuil's Trinidad, Ii84 t 

 pnge 431, reads : 



" The prosperity of the Colony had now reached its culminat- 

 ing poi/tt, Cacao selling at a very high price. Hut in the year 

 17 ~7 * according to Gan'dla, not a disease of the trees exactly, but 

 a blight attacking the pods ander certain atmospJt,eric injL 

 yed the crops" 



