78 Pink Disease of Plantation Rubber 



appears to check its progress. It has been urged that the diseased bark 

 should be removed before tar is applied or even that tar should first be 

 placed over the affected parts, the rotten bark removed, and then tar 

 subsequently applied again. These are excellent ideals and if expense 

 were no object would be strongly recommended. Experience has shown, 

 however, that where tar is applied thoroughly without previous removal 

 of diseased bark good results are obtained as long as the treatment is 

 renewed within a month if necessary. Trees treated with tar for Pink 

 Disease should be examined within a month, and if the fungus has 

 spread, tarring should be tried again. If two applications of tar are 

 found useless in checking the disease the affected parts should be cut 

 out and burnt. On several estates where this mode of treatment has 

 been adopted, Pink Disease has been reduced to a minimum. If tar is 

 used to check Pink Disease it is essential that the work should be done 

 under good supervision, for if done carelessly the money spent on it 

 will be wasted. It is important also that diseased trees should be 

 treated at an early stage. In certain cases, e.g. when the leaves of an 

 affected branch have died, it is obviously hopeless to apply tar. The 

 only thing to be done in such cases is to cut out and burn the diseased 

 portions. The use of a concentrated Lime-Sulphur mixture has been 

 tried instead of tar, but it is difficult to check the use of it and it is 

 readily washed off by rain, hence it is not a good substitute and is not 

 recommended. 



Planters sometimes have difficulty in burning diseased branches on 

 account of persistent rain. If it is impossible to burn the diseased 

 parts directly, they should be drenched with a 10 per cent, solution of 

 sulphate of copper, removed from the plantation and buried in the 

 ground some distance away from the rubber trees. It must be remem- 

 bered, however, that there is nothing so good as fire for the destruction 

 of fungoid pests. In this connection mention may be made of the fact 

 that another pink fungus, Oospora sp., which is harmless, usually 

 develops on wood in Malaya a few days after being burnt. This fungus 

 has been several times mistaken for Pink Disease. 



Where Pink Disease has appeared in an estate, a pest gang should 

 be formed if not already established and the size of the gang should be 

 such that it can go over the whole estate and treat diseased trees on 

 the above lines once every three or four weeks. Pink Disease develops 

 rapidly and any longer interval is too great to allow of it being dealt 

 with effectively. Where a considerable amount of Pink Disease is 

 present one can hardly expect to eradicate it completely so the expense 



