CHAPTER XII 



VEGETABLE PARASITES AND EPIPHYTES 



The dodder, Guscuta spp., and Loranthus leftolcbus are, 

 strictly speaking, only partially parasitic on the cocoa 

 tree, as they derive a certain amount of nourishment 

 from the atmosphere. The latter is usually propagated 

 on the cocoa tree by means of its seeds, which are 

 carried on to the branches by birds. The seed ger- 

 minates and its radicle penetrates the interior tissues 

 of the branch, where it obtains nourishment, and a 

 sucking organ develops at the expense of the cocoa 

 tree. Unless checked, Loranthus leptolohus forms dense 

 masses, often more than a foot in diameter, which must 

 considerably deplete the vitality of its host. This 

 parasite, therefore, should be cut out, and the wounds 

 thus made should be painted with the tar and resin 

 mixture. Epiphytes, such as mosses, lichens, and small 

 orchids, often interfere with the development of young 

 cocoa buds, and should be carefully removed from the 

 tree. Many of the cocoa trees in the hilly districts of 

 San Thome are badly infected with various forms of 

 epiphytes. The OrcheUa Weed is very common, and often 

 hangs down from the branches in masses a foot long. 

 Hariot identified two epiphytes common on cocoa leaves 

 in that island as Cephaleuros virescens, Kunze, and Phy- 

 copeltis flabdligera, Hans. Lichens, common on Ceylon 

 cocoa trees, are : Physcia speciosa and species of Lecani 

 and Bamdinia. 



Fungus Diseases of Cocoa. — A large number of fungus 

 pests attack the cocoa tree ; some of these are purely 

 local, whilst others, such as the "Brown-pod" disease of 

 the fruit, Thyridaria tarda, are almost ubiquitous in every 

 country where the tree is cultivated. 



It is not proposed to follow the practice adopted by 



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