CHAPTER XXX. 239 



The elements which largely destroy our forests are timber and 

 wood cuting, sheep herding and forest fires. 



While excessive cutting of timber or wood has a very bad result 

 upon the quality of our watersheds, the herding of sheep and the for- 

 est fires can rightly claim to be the most damaging elements. Sheep 

 will eat anything in their way and destroy all the underbrush, grass 

 and small growth on the watershed. In this way they decrease the 

 resistance of the surface against the running ofi of the water, in- 

 creasing the storm run-off from the watershed — which latter is an 

 entire loss to the irrigators. What is left after the sheep get through 

 is generally destroyed by the fires left by the herders. Forest fires 

 destroy all growth and prevent the young growth from coming up 

 for years; also, the ashes created by the same will seal up the pores 

 of the surface of the earth and seepage into the subterranean channels 

 becomes an impossibility, while floods become frequent and destructive. 



Again I will call your attention to the San Gabriel river and the for- 

 est fires on its watershed several years ago. After one of these large 

 fires I have noticed that by a subsequent rainfall upon this water- 

 shed, a small flood resulted, showing that almost none of the water 

 was absorbed by the surface of the watershed and all ran off in a 

 very short time. 



I have tried to express by the above statements the means of pro- 

 tecting our watersheds against the denudation, and to adopt such meas- 

 ures as are possible to create a new growth of trees wherever that can be 

 done, and to replace the forests previously destroyed in order to in- 

 crease the water supply for the valleys of Southern California, and, 

 besides. If possible, to give an additional supply for such acreage as 

 has not yet come under irrigation. 



A. H. KOEBIG, 

 Consulting Engineer, Los Angeles. 



