ATTACKING THE TRUNK. 19 



of the larva, and it has transverse rows of minute spines on 

 the back, and a few at the extremity of the body. 



Remedies. — The young larva, as already stated, may often 

 be detected by the discoloration of the bark. In such in- 

 stances, if the outer dark-colored surface be scraped with a 

 knife, late in August or early in September, so as to expose 

 the clear white bark beneath, the lurking enemy may be dis- 

 covered and destroyed. Later they may be detected by their 

 castings, which have been pushed out of the crevices of the 

 bark and have fallen in little heaps on the ground. When 

 first discharged, these look as if they had been forced through 

 the barrels of a minute double-barrelled gun, being arranged 

 closely together in two parallel strings. Those which have 

 burrowed deeper may sometimes be reached by a stout wire 

 thrust into their holes, or by cutting through the bark at the 

 upper end of the chamber, and pouring scalding water into 

 the opening, so that it may soak through the castings and 

 penetrate to the insect. 



Among the preventive measures, alkaline washes or solu- 

 tions are probably the most efficient, since experiments have 

 demonstrated that they are repulsive to the insect, and that 

 the beetle will not lay her eggs on trees protected by such 

 washes. Soft-soap reduced to the consistence of a thick 

 paint by the addition of a strong solution of washing-soda 

 in water is perhaps as good a formula as can be suggested : 

 this, if applied to the bark of the tree, especially about the 

 base or collar, and also extended upwards to the crotches, 

 where the main branches have their origin, will cover the 

 whole surface liable to attack, and, if applied during the 

 morning of a warm day, will dry in a few hours, and form 

 a tenacious coating, not easily dissolved by rain. The soap 

 solution should be applied early in June, and a second time 

 during the early part of July. 



