FOREST PROTECTION. 137 



ing may be resorted to, or bisulphide of carbon may be 

 used to suffocate them in their burrows. 



Birds. Most of our birds are helpful in various ways, 

 such as distributing seeds and in destroying injurious 

 insects, and such small injurious animals as mice and 

 gophers. They also add to the beauty of our woods 

 and fields, and to our pleasure and recreation. But 

 some kinds are provokingly injurious by eating the seeds 

 we wish to gather, or by digging up newly sown seeds. 

 Where they are troublesome on seed-beds, they may be 

 kept away by covering the bed with wire netting, which 

 will also serve to keep away other animals. If only birds 

 are troublesome, mosquito netting may be used, or the 

 seeds may be given a light coating of red lead and dried 

 in land plaster or flour before sowing. 



The sap-sucker does considerable injury to some trees 

 by making holes in the bark for the purpose of securing 

 insects which go there to feed on the sap. They are 

 sometimes so very injurious that it is necessary to destroy 

 them. The Apple, Box-elder, Maple, and most other 

 trees are subject to their injuries. 



Cattle. The pasturing of cows, horses, sheep, and 

 other animals in the woodlands is generally a poor practice, 

 as these animals browse off many of the young seedlings, 

 especially those of deciduous trees, such as the Oak, 

 Basswood,' Cherry, and others, though they seldom ea^ 

 coniferous trees. They also compact the ground, and de- 

 stroy many small seedlings by their continued tramp- 

 ing, especially when present in large numbers. This 

 is especially true of sheep on the Western forest reserves. 

 Deer, moose, elk, and other similar animals are likewise 

 injurious in forests, and when abundant may do much 

 damage, though on account of their comparatively small 

 number they seldom do more than slight injury. 



Forest and Pasture. When forests are used as pas- 



