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(b) Trees that are showing a few diseased leaves should be 



climbed, the diseased leaves cut down and burned. The 

 manager of the estate at Icacos has burned several trees 

 that have shown signs of disease, by sending a boy up 

 the tree, packing dry material in the lower leaf-sheath 

 bases and setting fire to the whole. This method, in 

 some instances, has given good results, for all the lower 

 diseased leaves have been burned and all the fungus 

 spores destroyed. Considerable damage, however, is 

 often done to the tree by this method and at least two 

 or three crops of nuts are destroyed. It would probably 

 be just as effective to cut down the diseased leaves and 

 burn them on the ground for in this way damage by 

 burning would not be done to the young parts at the 

 terminal bud. 



(c) It would be advisable to search through the plantation to 



see whether any isolated trees show the characteristic 

 broken-tips of the leaves with pustules on them, and if 

 such are found these trees should be marked on the stem 

 with a suitable mark so that they can be carefully 

 watched, as they may possibly be the source of infection 

 for another area. All leaves showing signs of disease 

 should be destroyed with fire and such trees should be 

 examined at least once every fortnight until no further 

 spread of the disease is observed. These trees should 

 be carefully attended to, manure should be given them 

 and the soil around them properly tilled, in order to 

 enable them to throw off the attacks of the fungus. 



(d) If the disease continues to spread, spraying with fungicides 



would render the spores of the fungus incapable of 



germination, and would therefore be effective in keeping 



the disease in check. The fungus is the most easily 



assailed through those portions of it that come to the 



surface — the spores, for their germination can effectively 



be prevented by the use of chemicals ; but the question 



remaining to be solved is how frequently it is necessary 



to apply such an external remedy. Without further 



information such a problem cannot be answered, but 



continued observation would soon reveal an answer 



to this important question. How soon after complete 



destruction of the spores will a fresh batch be produced 



on the same leaf ? This is the question to be answered 



and such an answer must be a guide to the frequency of 



the use of fungicidal spraying. 



Bordeaux mixture would probably be the fungicide that would 



be used the most economically, and spraying with this would 



need a spray pump and a long hose attached to the pump. The 



nozzle may be tied to the end of a long bamboo, or a boy may be 



sent with it up the tree in order that the highest tree could be 



sprayed. All trees showing any signs of disease and any in their 



immediate neighbourhood should be sprayed at frequent intervals 



