INSECT PESTS AND THEIR CONTROL 145 



ing trees to ward off attacks. Young trees are 

 naturally less robust than older ones, and the dry 

 season is the period when vigour is at its lowest 

 ebb. We have, however, become so accustomed to 

 see young Coffee here and there becoming infested 

 by scale in the dry season, and to see the scale 

 disappear from it again in the rains, that we re- 

 gard its appearance with equanimity. 



More noticeable than the scale itself is a black 

 fungus which grows on the excreta. This covers 

 the leaves of a badly infested tree, and will greatly- 

 hinder growth if allowed to remain for any time. 

 The fungus is known as {l Black Blight" or 

 "Sooty Mould." 



An effective spraying mixture is made by using 

 1 Ib. of whale oil soap in 6 gallons of water. For 

 the scale on Cocoa pods, Mr. Gowdey found this 

 mixture, used at double strength, at 10 day inter- 

 vals, moderately successful. 



A resin wash calculated to destroy scale by 

 asphyxiation is made as follows : 



Resin, 4 Ibs.; Seal oil, 2 pints; Caustic Soda, 

 1 J Ibs. ; water, 10 gallons. Boil until the resin is 

 dissolved, then make up to 15 gallons of water. 

 To use, allow 1 gallon of above stock solution to 8 



(D 243) L 



