282 AGRICULTURE 



has set apart sixty-one forest reservations, containing over sixty-one 

 million acres, at the head waters of streams and on high land in 

 the West. 



Forest Enemies. What are the chief enemies of the forest which 

 is so useful, so necessary to man? They are fungi, wind, insects, 



grazing and browsing animals, fire, and 

 man himself. 



Fungi. Like other plants of the 

 higher orders, trees have fungous pests 

 that cause decay and death. 



Wind. Windstorms often uproot 

 trees and in certain sections injure and 

 destroy miles of forests. 



Insects. Insects frequently kill trees 



ON AN OAK TREE 



ants and borers, burrow into the wood until it is honeycombed. 

 Others, such as the larvae of sawflies and moths, kill the trees by 

 destroying the foliage. 



Grazing. Wild and domestic animals do harm in various 

 ways. Pasturing in moderation is not harmful; but large 

 herds and flocks injure forest soil by trampling and close 

 grazing, and they bruise and break young trees. Sheep and goats 

 which browse on the foliage are most injurious. 



Fire. Next to man, the great enemy of the forest is fire. It 

 often sweeps over miles of land, killing young trees and injuring 

 old ones. In the decaying wood, worms finish the work of destruc- 

 tion begun by fire. Even the soil is destroyed by being deprived 

 of humus. 



Man. Man, directly or indirectly, is the most destructive of all 

 the enemies of the forest. He fells trees in vast quantities, and by 

 carelessness and bad methods he increases the harm done. He 



