46 THE RUBBER INDUSTRY 



and in neither country has any explanation of it been 

 found, except that it may be caused by the action of 

 rain-water on the newly-exposed inner layer of the 

 cortex. In Java it is attributed to canker, but there 

 everything is attributed to canker at present. Bacteria 

 and a Nectria have been found in these wounds in 

 Ceylon, but inoculations with both have failed to 

 reproduce the decay. 



" Hitherto it has not been considered advisable to stop 

 tapping when this decay appeared. Nor has it been 

 considered necessary to cut out the decayed cortex, 

 because the wounds made by cutting out were in many 

 cases larger than those which would have been caused 

 if it had been untouched. 



" A method of treatment, which is said to have given 

 good results, has, however, been adopted in Java, and, 

 as this decay has serious effects as far as regards the 

 renewed bark, it should be adopted here. The Java 

 treatment is as follows : 



" As soon as the narrow vertical lines are observed, 

 the tree is put out of tapping. The decaying tapped 

 surface is then washed every four or five days with a 

 50 per cent, solution of Carbolineum Plantarium. In 

 about four weeks the tree can be tapped again. If a 

 large patch has decayed, the dead cortex is cut out 

 before treating with Carbolineum." 



To treat forest trees scattered over a wide area in the 

 manner suggested by Mr. Fetch for plantations is im- 

 practicable as matters stand in Brazil at present, the 

 principal obstacles being the lack of intelligent super- 

 vision and the abnormally high rate of the daily wage 

 earned by labourers in the rubber-producing districts. 



