76 PrOCi:EDINGS 01^ THE 



Rainfall and Run-off During January, February, and 

 March, 1900. 



Run-off Run-off in 



per square percentage of 



mile. precipitation. 



A ere fe e t. Per cent. 



452- 35 



428- 2,Z 



557- 43 



828- 95 



"The most striking feature of this table as compared 

 with the previous one is the uniformly large run-oflf 

 as compared with the rainfall. This clearly shows 

 the enormous amount of water taken up by a dry soil, 

 either forested or non-forested, as compared with 

 one already nearly filled to saturation. During the 

 three months here noted, on the forested basins about 

 three-eighths of the rainfall appeared in the run-ofif. 



Rapidity of Decrease in Run-off After the Close of the 

 Rainy Season. 



Area of Condition Pre- April May June 



cipita- run-off run-off run-off 



tion. per sq. m. per sq. m. per sq. m. 



Inches. Acre feet. Acre feet. Acre feet. 



1.6 153- 65- 25- 



1.6 146- 70- 30- 



1.6 166- 74- 30- 



.53 Non-forested. i 56— 2- o 



"The above table clearly shows the importance of 

 forests in sustaining the flow of mountain streams. 

 The three forested catchment areas, v/hich, during 

 December, experienced a run-off of but 5 per cent, 

 of the heavy precipitation for that month and which 



