BORING INSECTS 69 



they enter the wood) it must be cut away and the 

 wound must be painted. 



If, on the contrary, probing the burrow is not 

 rewarded by that peculiar and gratifying sound 

 which makes known that the larva has been 

 crushed, poisoning must be resorted to. Carbon 

 bisulphide is almost invariably used for this pur- 

 pose, because of its cheapness and convenience. 

 It is a highly volatile fluid, giving off a gas which 

 is deadly to all animals. It is inflammable, and 

 he who smokes while he uses it had better look 

 out for the fool-killer. As a rule, it comes in 

 half-pint tins, stopped with a cork. There are 

 several ways of applying it to the burrows. I 

 carry around a pocketful of little bits of cloth, say 

 an inch square. When I have opened up the 

 mouth of a burrow I take one of these bits of cloth 

 with a pair of forceps, dip it into the carbon, and 

 then insert it in the hole, which is then, of course, 

 immediately plugged with putty. The more usual 

 way, though, is to apply the fluid with a small 

 syringe, those of glass being handiest. About 

 half a teaspoonful or a little less is required for 

 each hole. 



It is extremely essential, in going over a tree, 

 that every burrow be found, and that the eye be 

 trained to detect the least indication of the pres- 

 ence of a borer. Every suspicious-looking spot 



