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Nature of soils as affecting the abundance of T. Gestroi. 
In view of the fact that the termitaria are contained 
invariably if not exclusively in timber, it may be concluded 
that soils only indirectly effect the abundance of T. Gestroi, 
i.e. certain soils are favourable to the growth of trees 
affected by T. Gestroi . 
The soils may affect the extent of the attack on rubber 
trees by being more or less easy of penetration when the 
termites go abroad in search of food, * 
Methods of extermination, 
On old rubber trees. It has to be determined whether 
1. Gestroi establish their termitaria in the rubber trees 
themselves and on this point I have no data. If it should 
prove to be the case, fortunate is he who discovers an in- 
secticide, or other means, by which the Queen cells may be 
reached, at a low cost and without destroying the tree, ‘and 
thereby obtain the reward now being offered. On the 
other hand, our success in exterminating the pest depends 
upon the skill with which the runs are traced up to their 
base If all timber is collected and destroyed I feel con- 
vinced that if the attack does not entirely cease it will be 
very much diminished. 
On young Rubber Estates. I have found it cheapest 
and best to make a systematic search held by field and line 
by line for all timber which is known to be favoured bv T 
Gestroi, cut them open with an axe or cross-cut saw and if 
they contain the slightest trace of the enemy destroy them 
by burning. 
The danger of scorching the surrounding plants may 
be entirely done away with or at least greatly minimized 
by burning m a trench, keeping the fire covered with green 
stuff, and shielding the surrounding trees with sheets of 
corrugated iron. 
These should not lean against the rubber trees but be 
supported by sticks a short distance from them; even if two 
or three rubber trees are destroyed bv fire in this way the 
damage done is more than compensated for, bv the fact that 
one 1 . Gestroi termitarium is capable of destroying a score 
or more of trees to a distance of two or three hundred feet. 
Where there is a sale for timber or charcoal, sound 
Meranti trees may be sawn up with advantage and Kumpas 
can be converted into first class charcoal 
