SURVEYS OF FOREST RESERVES. 107 



throughout the reserve, but the old trees usually survive in spite of 

 them. Z^fevertheless the damage done to the growth of timber and the 

 reijroduction of the forests is very marked, and, in addition to the sur- 

 face tires, cases are not rare where the forest has been wholly destroyed 

 by fiercer conflagrations. The surface soil in this range is granular or 

 powdery, and excessively dry when deprived of its covering of humus, 

 and the damage which the fires do has reference in the uiajority of 

 cases to their effect upon the soil. 



Fites are dangerous throughout the dry season, and their prevention 

 is a matter of considerable difficulty. That it is possible to check 

 them, however, is abundantly demonstrated by the results of the pro- 

 tection afforded in the Yosemite, General Grant, and Sequoia National 

 Park by troops of the Eegular Army. 



WATER. 



The agricultural prosperity of the San Joaquin Valley depends 

 almost entirely upon the streams which have their rise in the Sierras. 

 The interests at stake are exceedingly large, and they have influenced 

 public opinion in California to a marked degree. The intimate relation 

 between the forests and irrigation led the California delegation in Con- 

 gress to object to the suspension of the reserves established by Presi- 

 dent Cleveland in their State, and as a consequence the California 

 reserves are intact. Floods have already begun to demand attention 

 in various parts of the State, and the protection of the Sierra forest is 

 urgently required both to maintain and to control the water supply. 



Mining retains but little development in the Sierras now that the 

 placers of the foothills have been exhausted, and no difficulty in the 

 management of the forests is anticipated on this score. 



AGRICULTURE. 



Agriculture does not and can not exist within the reserve except 

 over very limited areas within a few of the canyons, the total of which 

 is so small as to require very little special consideration. 



Grazing has taken on its chief importance through the extensive 

 pasturage of sheep over the whole area of the Sierras, except where it 

 has been controlled and prevented by United States troops. The result 

 of sheep pasturage upon the dry, loose soil of these mountains is most 

 serious. Forest reproduction is difficult atthe best in the higher portions 

 of the mountains, and sheep render it wholly impossible wherever they 

 pass. The loosening, and even transportation, of the upper soil by their 

 feet goes on to an extent difficult to conceive of until it has been seen. 

 I have found a wagon road rendered almost impassable by the stones 

 pushed into it from the hill-side above by the passage of a band of sheep. 

 During a trip across the Sierras on foot it became exceedingly diflScult 

 to follow the trail wherever these animals had passed. The harm sheep 

 do in the Sierras is far greater than that known to me in any other 

 region in the United States, and it is imperative that they should be 



