WEST VIRGINIA EXPERIMENT STATION 



all stages and examples of the destructive bark beetle, in the 



winter of 1892-3 throughout the infested area. 



The apparent con- 

 tinuation of the 

 trouble to 1896 was 

 simply the gradual 

 dying of injured 

 trees from subse- 

 quent and succes- 

 sive attacks of 

 other species of 

 bark beetle, which 

 prefer to attack in- 

 jured, diseased or 

 felled trees. 



FURTHER TROU BLE 

 PREVENTED. 



The attack on the 

 remaining healthy 

 pine and spruce by 

 the surviving spec- 

 ies of bark beetles, 

 which were capable 

 of attacking and 

 killing trees, was 

 evidently prevented 



Fig. LIL A forest of table mountain pine on north- Qy the Common OC- 



western turnpike, Allegheny front. Seven years 



after it was killed by the destructive pine bark bee- CUlTence of injured 



trees in the spring 



of 1893, and the great quantity of tops, logs and stumps of recent- 

 ly felled trees that subsequently occurred in the numerous 

 lumbering regions throughout the pine and spruce area, which 

 attracted the threatening beetles away from the living timber. 



AREA INVADED BY THE DESTRUCTIVE BARK BEETLE. 



As near as I can ascertain, the total area, including portions 

 of West Virginia, Virginia, Maryland, Pennsylvania, and pro 



