107 



ally girdle and kill the parts attacked. Badly infested trees begin to die 

 at the top, and in a few years the trees succumb. By the time the tops 

 turn red and die the trees are hopelessly injured, and the borers can usually 

 be found in all parts of the trunk. Their location is detected from the 

 reddish patches on the bark caused by the oxidizing sap flowing from the 

 borings. 



Control Measures. — It is difficult to preserve imported white birches 

 in localities where these beetles are abundant. At the first appearance 

 of injury the infested tops and infested branches should be removed and 

 burned before the beetles appear from the wood, late in May or early in 

 June, to spread the infestation. After much of the top has died from the 

 attack of the beetles, it is usually hopeless to attempt to save the tree by 

 repeated by pruning off the dying upper portion. The whole tree is by that 

 time a breeding ground for the pest, and if other imported birches are to 

 be saved the badly infested trees would be much better cut and burned 

 before the middle of May to destroy the beetles contained. 



The native birches are attacked by the beetle, but are much more 

 resistant, and injury to them is less commonly seen. 



The Locust Borer, CyUene robiniac, is a most destructive enemy 

 of the black locust. The adult is a black and yellow long-horned beetle, 

 about three-fourths of an inch in length, frequently found on the flowers 

 of golden rod in September and later. The females deposit their eggs 



Work of the locust borer, CyUene robiniae. 



