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FOREST PROTECTION 



5. The white pine weevil kills the leader or tip of the common 

 pines of the East except red pine. Norway spruce is also badly 

 injured. 



6. Western pine bark beetle destroys over two hundred million 

 board feet of the best ponderosa pine annually. 



7. The mountain pine beetle destroys enormous quantities of lodge- 

 pole pine in the Rocky Mountains each year. 



p IG 44. Peeling the bark from insect-infested ponderosa pine in a western 



National Forest. Two men on the left are using bark spuds, the man on the 



right has a peavy, which is used to roll the log down to a landing. 



8. Other important examples of insect pests are the locust borer, 

 which riddles the heart and sapwood of locust, with the result that 

 this valuable tree is discredited for planting in some regions; the 

 catalpa sphinx, larch sawfly; and the hickory bark beetle. 



The marine borers, namely, teredo and limnoria, are mollusks and 

 not insects; they have destroyed large quantities of piling, harbor 

 improvements, bridges, and vessels and are a serious problem for the 

 zoologist and timber preservation engineer. 



The Division of Forest Insects in the Bureau of Entomology and 

 Plant Quarantine in the U. S. Department of Agriculture devotes its 

 activities to the investigation of forest insect problems and cooperates 

 closely with the Forest Service, the National Park Service, Bureau of 



