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has been observed that there is a marked tendency for the disease 

 to spread from centres of infection and, as mentioned previously, 

 it appears that the disease is spreading rapidly towards the 

 southern end of the island, probably from the Guapo district. 



I am of opinion that it should be made compulsory for every 

 cultivator of coco-nuts, no matter to however small an extent, to 

 destroy by fire or otherwise all dead and dying trees on his grounds. 

 The loss on some of the Cedros estates fully shows the destructive 

 nature of the disease and therefore drastic measures must be taken 

 or otherwise the industry must suffer considerably. 



2.— ISOLATION OF DISEASED AREAS. 



The disease generally appears, at first, in small patches, while 

 the surrounding trees are apparently unaffected. As the myce- 

 lium of the fungus may spread through the soil, these diseased 

 areas may be isolated by cutting trenches from I foot to 18 inches 

 deep around them. It must be remembered that the mycelium 

 may have spread further than is noticeable on the trees and, 

 therefore, the trench should be made to include several trees 

 that are apparently healthy, and care should be taken to throw 

 the excavated soil into the diseased portion and not outside it. 

 Such a method of isolation, especially where the diseased areas 

 are small, cannot be too highly commended in dealing with 

 root-diseases, but the amount of success depends entirely on the 

 thoroughness with which the work is carried out. In any case it 

 may prove to be a very good method of confining the disease to a 

 limited area. 



3.— RESTING OF INFECTED LAND BEFORE PLANTING SUPPLIES. 



Young supplies that have been planted in infected land have 

 shown that they have been attacked by the fungus and, therefore, 

 it would appear necessary to rest such land for a series of years 

 after removal of diseased material before commencing to replant. 

 In this way it is hoped that the fungus mycelium may be starved 

 out, and at the same time it affords an opportunity for careful 

 cultivation of the land. Such land should be turned up, either 

 with the plough or with the fork, so that the fungus mycelium 

 may be turned up and exposed to the destructive action of the sun, 

 and when supplies are put in they should not be planted in the 

 old rows, but rather between them, so that the new plants alternate 

 in chess-board fashion with the spots whence diseased trees have 

 been taken. 



The careful cultivation of the land before replanting should im- 

 prove the condition of the soil and possibly green dressings of 

 some leguminous plant might be profitably grown and ploughed 

 in. Some of the soils are already rich in organic matter and here 

 some remunerative rotation crops might be grown on badly infected 

 lands for a year or two before planting the young supplies- 



4.— SPRAYING AND APPLICATION OF CHEMICALS. 

 When diseased trees are cut down and destroyed there may be 



