244 A YEAR IN AGRICULTURE 



every hundred tons of coal mined, two tons of mining timber 

 are needed. For our means of transportation we rely mainly 

 on wood. Millions of telephone poles are needed to keep up 

 our communications. The forest furnishes the wood for all 

 the implements of the farm, and for all vehicles of trans- 

 portation there. Lumber is not the only product of the forest. 

 There is the turpentine of the pine, the paper pulp of the 

 spruce and poplar, the tan bark of the oak and hemlock, the 

 sugar and syrup of the maple, and the various distilled prod- 

 ucts from many other species. The alarming fact about the 

 use of forest products is that we are using wood three times 

 faster than it is growing. 



Forest influences. In addition to serving as a great source 

 of wood supply, the forest exerts certain influences on human 

 interests. These are influences: 



1. Upon the climatic conditions within the forest area. 



2. Upon the distribution and character of the water flow. 



3. Upon the mechanical condition and erosion of the soil 

 under its cover. 



4. Upon the sanitary and esthetic conditions of the people. 

 About the only influence the forest has upon climate is to 



keep it more uniform within its own limits, and to shelter our 

 homes from storms and winds. The forest's greatest influ- 

 ence is upon the distribution and character of the water flow. 

 The forest crown and floor catch and hold the rainfall, and 

 allow it to sink slowly into the ground to supply a uniform 

 flow in springs and streams, at the same time preventing 

 destructive floods and excessive soil washes. The forest air 

 and water are pure and healthful, and the tired city dweller, 



