82 



SHADE TIZEES. 



BORERS. 



A variety of borers infest shade trees and, as a rule, they 

 attack, by preference, such as are weak and sickly. But 

 that is by no means a universal rule. Maple 

 trees are not infrequently infested by a small 

 caterpillar borer that works into the heart-wood 

 though it does little damage unless water finds entrance 

 through their holes and causes decay. (See page 119.) The 

 holes through which they emerge are not over % inch in di- 

 ameter and nearly round. The moth is a pretty, clear- 

 winged species, yellow, with bright red markings. 



Usually 

 attack 

 weakened 

 trees. 



Fig. 34. The Maple Tree Sesiid : a, the larva ; 6, cocoons in cavities made 



by larvae ; c, the adult moth ; d, pupa-shell projecting from trunk. 



After Riley. 



As against this species frequent whitewashing the infested 

 trunks and sealing up the holes with putty, is about the only 

 thing that can be done, unless there is a decayed area acting 

 as the centre of infestation. In that case the cavity should 

 be thoroughly cleaned and treated as described on page 45. 



