52 
carbolineum or some other disinfectant. After a few weeks tapping* 
can be started again ; in some cases it 'is not necessary to stop 
tapping.” As preventive measures they point out that free access of 
air and light should be given to the trees in the plantation by 
thinning out, that there should be a thorough system of drainage 
and the use of water in tapping should be avoided, 
Dastur, who did the work on the disease in Burma, suggests 
cessation of tapping at the first appearance of the disease and the 
collection and destruction of all diseased fruits. 
In South India an effective method is said to be the ee-sation of 
tappiug on affected trees and a mixture of tar and tallow smeared 
over the diseased area of bark. 
Fetch says “ When the tapped surface shows s'igns of decay it 
should be brushed over twice a week for three weeks with a solution 
(20 per cent.) of brunolinum (brunolinum one gallon, water four 
gallons, soft soap one lb.) The canker patches must be cut out and 
the diseased tissue burnt.” 
I have not as yet been able to draw any very definite conclusions 
from the experimental treatment adopted on the various estates 
affected but hereunder I make suggestions which may be acted upon 
at once should the disease be found on your estate. 
Prior to making suggestions it is necessary to understand the 
conditions which favour the growth and spread of the fungus. 
All species of Phytophthora, the potato disease of Ireland caused by 
Phytophthora infestnns is one example, need excessive humidity for 
their development. Any particular cause which has the effect of 
preventing the drying up of moisture on the tapping or tapped 
surface should he eliminated if such elimination is possible. One 
cannot prevent rainfall but it is possible by one or more of several 
means to increase the rate at which the moisture on the bark will 
evaporate. 
It does not follow that because a method of treatment is 
successful in one country it is necessarily a success in another 
country or another part of the same country because conditions, 
particularly atmospheric conditions, vary so considerably. 
In Burma, for example, there is a distinct wet season and 
it is. during this season that the disease is prevalent. In this 
country again it seems to me that the fungus, for some unexplained 
reason, penetrates more deeply into the tissues of the plant, to a 
considerable depth in the wood, than, from the information obtain- 
able, in other parts of the East, where Hevea is planted. It w*ould 
appear then that what may be an unavoidably drastic measure in one 
place could be extremely unnecessary in others even in the same 
country. 
