A BOTANICAL SURVEY OF SAN JACINTO 



MOUNTAIN.* 



INTRODUCTION. 



Selection of San Jacinto Mountain. 



Extending across Sonthern California in an irregnlar line 

 from the point where the Sierras and the Coast Ranges meet, 

 nearly to the southeastern corner of the state, a series of moun- 

 tain ranges separate the dry interior deserts from a much more 

 moist but still arid region bordering on the Pacific Ocean. 

 Raising their summits above the lesser mountains and ridges of 

 these ranges, a few peaks stand out like sentinels and serve as 

 land-marks for all the surrounding country. The southernmost 

 of these high peaks is San Jacinto Mountain which, with its 

 altitude of 10,805 feet, is separated from all the others by low 

 passes and ridges the highest of which is under 4000 feet in alti- 

 tude. 



In considering this mountain as a field for liotanical explora- 

 tion it was noticed that its position at the southern extremity of 

 the higher ranges would make it the southern limit for many 

 boreal species. It was also noted that the proximity of the Col- 

 orado Desert would give to its fiora a strong austral element, and 

 that its isolation from other mountains would render more defi- 

 nite certain problems connected with the geographic distribution 

 of plants. For these reasons, as well as for a number of others 

 of minor importance, San Jacinto Mountain was finally sele(;ted 

 for botanical investigation. 



Region Covered and Collections Made. 



In the course of this survey practically all parts of the moun- 

 tain, with the exception of a small area in the chaparral belt of 



* Presented in partial fulflllraent of the requirements for the degree of M.S., 

 University of California, May, 1902. Prepared under the direction of Professor 

 W. L. Jepson. 



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