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YEARBOOK OF THE DEPARTMENT OF AGRICULTURE. 



die, while the lower branches and trunk may remain in normal health. 

 Sometimes the entire tree is killed the first season, but more often the 

 lower portion dies from a subsequent attack. Upon examination there 

 will be found the wounds made by the beetles ajb the base of the buds, 

 which cause the leaves to die or fall. Upon removing the bark from 

 the dead branches the characteristic brood galleries will be found in 



FIG. 28. Complete brood galleries of the hickory bark-beetle in surface of wood. (Original.) 



the inner bark and engraved on the surface of the wood (tigs. 27 and 28). 

 If the tree is infested the parent beetles will be found in the primary 

 longitudinal galleries, and great numbers of small, white grubs in the 

 larval burrows in the bark. If the broods have emerged, the bark will 

 be found perforated with numerous small round holes, as indicated in 

 fig. 29. 



