52 TREE WOUNDS AND DISEASES 



Maltreated trees in parks and commons 

 frequently become the prey of several boring 

 beetles, especially the goat and wood leopard 

 moths and the elm bark beetle. The two 

 former attack both injured and sound timber, 

 and in the case of the goat moth in particular 

 branches become so weakened by the tunnel- 

 ling that they snap across in stormy weather. 

 Careful examination will alone reveal the pre- 

 sence of the goat and wood leopard moths, as 

 the mouth of the entrance hole or tunnel is 

 frequently filled with plastic sawdust. By 

 clearing out the holes and inserting a small 

 quantity of cyanide of potassium, the pests will 

 quickly be eradicated. Where the elm bark 

 beetle is abundant, the best remedy is to strip 

 off and burn the loose bark, and in the case of 

 badly affected trees to remove these wholesale. 



Squirrels, hares, rabbits, voles, and mice 

 frequently attack the bark of trees, both young 

 and old ; but, as their depredations are con- 

 sidered in the chapter devoted to " Injuries 

 from Animals and Birds," they need not 

 receive attention here. 



Bark-scorching produced by the rays of the 



