306 The Farm Woodlot 



months the stream bed was dry. The forested water- 

 shed, on the other hand, absorbed the rainfall in the way 

 described above, and, though there was high water in the 

 creek during the rainy season, there was no flood to injure 

 improvements along the banks. At the close of the rainy 

 season, there was very little decrease in the volume of 

 stream flow and a fair amount of water flowed in the 

 stream bed throughout the dry season, when water is 

 most needed and most valuable for irrigation purposes. 



Perhaps as much water comes down from the bare water- 

 shed in the course of a year as from the forested one; 

 in fact, probably considerably more water comes from the 

 former, for there are several factors that tend to dissipate 

 a part of the water that falls on the forested shed. A 

 part of the water the lighter the rain the larger the 

 percentage is intercepted by the crowns of the trees and 

 evaporates before it reaches the ground at all. It is also 

 a well-known fact that more moisture evaporates, through 

 the transpiration of the leaves, over an area covered with 

 vegetation than from a bare surface. Also, in the forest 

 the water is held in the ground so much longer than in the 

 open that there is more opportunity for evaporation in 

 that way. Thus, the actual amount of water in the forest- 

 born stream in the course of a year is really less than in 

 those coming from the bare country; but seventy-five 

 per cent of the latter is lost' in flood, is of no value for irri- 

 gation purposes or water power and does much damage 

 to improvements along its banks, while all the former can 

 be utilized all the year round and there is no damage to 

 adjacent property. 



Since the cutting of the forests at the headwaters of 



