SIERRA NEVADA PLANTS IN THE COAST RANGE. 



BY KATHARINE BRANDEGEE. 



The great valley of California is a basin or plain irregularly 

 elliptical in shape and about five hundred miles in length by 

 one hundred in breadth. It is rimmed all around with mountains, 

 the only opening being that from which all the waters of the 

 basin escape to the sea. The northern half of the valley, drained 

 by the Sacramento and its tributaries, is called the Sacramento 

 Valley; the southern half, drained by the river of that name, is 

 called the Valley of the San Joaquin. The slope of the land is 

 to the centre, where the two rivers meet and pour their mingled 

 waters into the Bay of San Francisco. The rim of the valley is 

 highest where the Sierra Nevada makes its eastern wall, even 

 the Truckee Pass, where the Central Pacific Railroad crosses 

 it, being over seven thousand feet in altitu-de. The southern 

 wall, formed by the Tehachapi Range, is nearly four thousand 

 feet in its lowest passes; the northern, formed by the Shasta Range 

 is but little less, and the western, though lower, is double, with a 

 long valley or series of valleys intervening, the inner, at least in 

 the northern half, having many peaks of considerable altitude, 

 Yolo Bolo being over eight thousand feet, Sanhedrim, Hull and 

 Snow Mountain between six and seven thousand. 



Seeds transported by whatever agency must find suitable 

 conditions or they will not thrive, and to this fact, of course, we 

 owe the diversity of flora still existing. The broad hot valley 

 of California offers no suitable home for the plants of the Sierra 

 and they cannot cross it. The valley plants cannot endure the 

 cold of the mountains, and if they flourish for a season even their 

 seeds succumb to the winter frosts. 



It is perhaps from a consideration of the barrier interposed 

 by this vallej^ that the flora of the Sierra Nevada has been con- 

 sidered to be so difierent from that of the Coast Range that 

 surprise is often expressed at the finding of additional species 

 common to both. It is, however, easily understood that plants 

 may follow the valley wall in any direction and for a distance 

 limited only by comparative height and consequent degree of heat. 



The localities of plants should be observed and recorded at 



