228 



THE FORESTER. 



September, 



! ! 



current is checked. These floods, entering 

 the artificial reservoirs, are brought to a 

 halt and quickly lay down their load, 

 forming a coating, or layer, of mud in the 

 reservoir, tending to greatly diminish the 

 storage capacity. If the water comes from 

 forested slopes, where the soil is protected 

 and held by roots, the amount of sediment 

 may be negligible ; but if, on the other 

 hand, these forests are cut away, the under- 



brush and humus burned, the driving- 

 storms soon attack and move the loose earth 

 and disintegrated rock, starting it on its 

 journey down the slopes, to be finally caught 

 in the reservoir below. Thus it happens 

 that it is of first importance for the pro- 

 longed life of the reservoir that every care 

 should be taken to perpetuate the forest 

 cover upon the catchment area, wherever 

 this can assist in holding the soil. 





BURNT-OVER HILLSIDE IN BITTERROOT VALLEY, BITTER ROOT FOREST RESERVE, MONTANA. 

 TIMBER BURNT OFF TWENTY-FIVE YEARS AGO AND NO REFORESTATION. 

 LACKS PROTECTION FOR SNOW OR RAINFALL- 



