CHAPTER VI. 

 NATURAL ENEMIES OF THE FOREST. 



The natural enemies of the forest as distinct from its human 

 enemies fall into three groups: (1) Meteorological, (2) Vege- 

 table, (3) Animal. 



METEOROLOGICAL FORCES. 



Wind. ''Windfalls" are not an uncommon sight in any forest. 

 Frequently only small areas arc blown down, one large tree upsetting 

 a few others, or again a vast region is destroyed by great storms, 



Fig-. 74. Effect of Wind, July , 1902, Cass County, Minnesota. 

 U. S. Forest Service, 



tig.. 74. An area of many square miles in Florida covered with 

 long-leaf pine was thus destroyed several years ago. The "slash" 

 thus formed, when well dried, is particularly liable to catch fire and 

 burn furiously. Windfalls are especially common among shallow- 

 Booted trees, as hemlock, basswood and spruce, on sandy soil and on 



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