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can be made to serve. Hence from one mature colony, inside or 

 just outside a clearing, a considerable percentage of the logs and 

 stumps may be infected. Allow one or two years of undisturbed 

 development, and you have numbers of colonies at great strength, 

 ready to attack rubber or any other suitable material, or to spread 

 the infection by swarms of flying individuals to uninfected areas or 

 logs. Trenching, digging, poisoning, fumigating, tracing runways, 

 and numerous modifications and combinations of these had been tried 

 and found incapable of eradicating the pest. Deep changkolling 

 over attacked areas had been abandoned — if it was ever tried — 

 probably because of the cost. In some places the surface timber 

 was being hunted through for nests, the logs cut open and the 

 queen sought and killed. As it had been frequently stated that 

 Termes gestroi had not the power possessed by a lot of species of 

 elevating baby commoners to the position of temporary queen, this 

 looked likely at least to stop any furtlier development of those nests. 

 But this method had soon to be discarded also, as 1 found, in the 

 remnants of such colonics, substitution queens raised either- from 

 undestroyed eggs or very young individuals. It was, therefore, 

 obvious that the whole nest must be destroyed so that no remnant 

 capable of raising substitution queens was left ; and not only the nest, 

 but the containing timber, lest later some members of a nuptial 

 swarm should find it a suitable place in which to settle and 

 recommence the trouble. But if in the remains of the nest log, why 

 not in other timber also. So long as suitable timber is left, even if 

 all the Termes gestroi in the clearing have been destroyed, the 

 conditons approximate to those of an uninfected new clearing, and 

 in one night a nuptial swarm may reinfect the whole area. 



I was thus driven to the conclusion that the only safe preventive 

 and remedial treatment for Termes gestroi was absolute clean 

 clearing. 



During 1915 I was able to test the method on a peaty block 

 suffering from the heaviest pure Termes gestroi attack I have seen. 

 Surface timber was destroyed, stumps were blasted and lifted, and 

 buried logs were prospected for with probes, dug out, and burned. 

 The work was done thoroughly, and the result was excellent. One 

 or two small areas showed re-attacks which were traced to hidden 

 logs, but after these were taken out, no further white ant trouble 

 arose in the block although pi'eviously the mortality ranged up to 75 

 per cent, of the 18 months old rubber. The method, then, was 

 sound, but what of the expense ? Would it really pay the average 

 estate to put up the necessary money ? I had faith that it would, 

 considering the crop saved, and the reduction in working costs 

 effected, so thereafter, whenever called upon to advise on white ant 

 treatment, I insisted upon the fundamental importance of destroying 

 timber. Some estates provided for the work — others carried on with 

 careful application of their previous methods. But during 1914-15 



