average. Not only is the standing timber destroyed by these fires, 

 but the young reproduction as well, and sometimes the very soil 

 cover that makes the forest possible is destroyed if the fires are 

 severe or repeated. These fires could be prevented at a cost of less 

 than ^ of the amount destroyed annually! 



It is said that of every 1000 board feet of standing timber, only 

 320 board feet are used by the consumer. The rest is lost in waste- 

 ful logging, and by fire, insect and fungus damages. 



By careful use, and the practice of forestry, we could easily pro- 

 duce more than four times the present growth, or enough to more 

 than supply our present needs. 

 Biologic. 



The efifects of forests on precipitation is of very minor importance. 

 May increase as much as 25%. 100% in forest, 93.9 on edge, and 

 76.7 outside. We do know, however, that where the greatest forest 

 areas are there is also the greatest precipitation. It is quite likely 

 that the forests are a result of the rainfall, rather than the reverse ; 

 but that they have an influence in concentrating rainfall when con- 

 sidered over large areas, there is little doubt. The condensation of 

 moisture on the leaves and branches in the forest amounts to from 

 .4 to .8 inches per annum, and the greater humidity, together with the 

 dampening and cooling of the upper air, has a tendency to increase 

 the amount of precipitation. Large bodies of forest, moreover, 

 check the winds and clouds, forming a mechanical hindrance, and 

 tend to create counter currents which again bring about the same 

 results (effects greatest at high elevations). 



Whatever the relation of forests may be to the precipitation, 

 there is no question as to their importance in the disposal of this 

 precipitation. Precipitation is in two forms, rain and snow ; and 

 the amount of the two taken together is remarkably constant each 

 year, though the time of distribution by months or seasons may vary 

 considerably. The disposal of the precipitation takes place in three 

 distinct ways : 



I in evaporation — the fly-off (which may be even greater than 

 the precipitation). 



■J flows to the sea — the run-off. 



^ consumed or absorbed — the cut-off. 



The effect of forests has been unquestionably proved to be to save 

 from the first two of these losses and to add to the amount absorbed. 



The forest forms a sort of matt or sponge in which precipitation 

 is caught and held, first by the leaves and twigs and stems of the 

 trees, and then by the covering of leaves, twigs, moss and humus 

 on the forest floor; and through this it seeps slowly into the soil 

 until the latter becomes thoroughly saturated. In this way the 

 moisture is held and accumulated in underground waters, which 

 go to feed the uniform flow of streams and springs in dry weather. 



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