CHAPTER VII 



INSECTS AND DISEASES THAT DESTROY 

 FORESTS 



Forest insects and tree diseases occasion 

 heavy losses each year among the standing mar- 

 ketable trees. Insects cause a total loss of more 

 than $100,000,000 annually to the forest products 

 of the United States. A great number of destruc- 

 tive insects are constantly at work in the forests 

 injuring or killing live trees or else attacking 

 dead timber. Forest weevils kill tree seeds and 

 destroy the young shoots on trees. Bark and 

 timber beetles bore into and girdle trees and de- 

 stroy the wood. Many borers and timber worms 

 infest logs and lumber after they are cut and 

 before they are removed from the forest. This 

 scattered work of the insects here, there, 

 and everywhere throughout the forests causes 

 great damage. 



Different kinds of flies and moths deposit 

 their eggs on the leaves of the trees. After the 

 eggs hatch, the baby caterpillars feed on the 

 tender, juicy leaves. Some of the bugs destroy all 



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