14 INTRODUCTION. 



thus allows the water delivered to flow across and beyond the great 

 natural reservoirs of our largest springs and streams. These are what 

 we call the second tier springs. One o£ the largest of these is a tier 

 of springs supplying the Los Angeles river and constituting the do- 

 mestic supply of this large city and of the irrigated vegas to the south. 

 Whenever a watershed is burned over we see the mountain streams ex- 

 tend their flow beyond the usual limits because of this channel cement- 

 ing. Thus on a light rainfall we see streams flowing clear across the 

 natural reservoir when without such fires only long and continuous 

 rains produce this result. In this country it is a misfortune to have 

 storm water flow off. We want it to sink in so that the perennial 

 springs can be supplied. It requires a heavy flood rolling the gravel 

 and boulders about to break these ash-cemented channels up so that 

 they can again absorb the torrent flow. This is one of the serious 

 dangers growing out of our mountain forest fires. The watershed 

 fires affect the first tier of mountain springs disastrously. The reduc- 

 tion in permanent water flow from these springs by such fires is from 

 one quarter to three-quarters of the regular supply. Comparing the 

 flow from the Deer Creek Springs with water-shed unburned with 

 springs on each side of it and on burned districts for the past two years 

 of light rains we find a slight shrinkage in the Deer creek supply and 

 a frightful shrinkage in the springs from the burned water sheds. The 

 exact figures are: Burned watershed, Cucamonga Canyon — Ordinary 

 flow, 210 miners' inches; after fire, reduced to 29 inches. Burned over 

 and second growth again burned on Alder canyon — Former flow, 6 

 inches; after fire, — or absolutely nothing. Deer creek canyon, un- 

 burned, ordinary fiow, 48 inches; in present dry year flow, 40 inches. 



These and other cognate subjects on which I have extensive notes 

 are more fully discussed in this volume under appropriate heads. 



Tree planting in Southern California has been more general than 

 in any district with which I am acquainted. The entire aspect of the 

 country has been changed. The objects of the forest tree planting were 

 for roads, wind breaks and fuel. At present the large eucalyptus 

 groves have become valuable for piling. The leaves of the Eucalyptus 

 are also used by several local establishments for the medicinal oil and 

 for eucalyptol. These trees and the Acacias grow with wonderful 

 rapidity and insure a fair fuel crop at seven years and a good one at 

 ten years. 



The Forest societies of the South have this year started to replant 

 portions of the burned areas of the Sierra Madre with indigenous 



