r 





VEGETATION OF INTRAMOXTANE CALIFORNIA. 



and Boreal zones, and a portion of the Upper Sonoran also, were cov- 

 ered with snow, so that only their arboreal vegetation could be seen. 



On the western slope of the Sierra Nevada the Transition zone is 

 marked by the presence, as already stated, of a belt of Pinus jeffrcyi 

 and another of Finns ponderosa. The Boreal zone is represented by 

 Abies magnified^ Pinus monticola, P. murrayana, and P. baJfouriana. 



The most conspicuous differences between the floras of ultramontane 

 and intraniontane California 1 are to be found at low altitudes, the Upper 

 and Lower Sonoran zones on the one side being correlated respectively 

 with the chaparral and foothill belts on the other. 



The chaparral belt of the western slope of the Sierra Xevada lies next 

 below the belt of Pinus ponderosa, or farther south, where this tree is 

 wanting, below the belt of Pinus jeffrcyi. It is a dense growth of shrubs 

 or small trees often so closely set as to be almost impenetrable. In the 

 upper portion of the belt the plants are of smaller stature and more 

 intricate growth, while toward its lower limit some of the species, like 

 Quercus chrysolepis, become trees of large dimensions. The principal 

 woody species characteristic of the chaparral belt are as follows: 



Adenostoma fascAeulatnm. Garrya vealchii. 



Aretostaphylos . Pinus sabiniana. 



Ceanothus rcslitus. Quercus breiveri. 



Cercocarpus parvifolius. Quercus chrysohpis. 

 Fremontodendron californieum. 



The foothill belt lies between the chaparral on the one hand, and 

 the valley-bottoms of the intraniontane region on the other. Its 

 woody vegetation is much more open than that of the chaparral belt, 

 but of different species, as follows: 



JEsculus californica. Quercus donqlnm. 



Ceanotluis cuneatus. Quercus lobata. 



Ceanoth us divaricatns. Mamona poiystutliya. 



Lonicera interrupta. Hints diversiloba. 



Lonicera subspieata- Salvia mellif era. 

 Prunus ilicifolia. 



The surface of the Tulare Plains, except the alkaline bottoms, con- 

 tains no shrubs, but a scant growth of herbaceous vegetation made up 

 principally of annuals, with a few perennial species, such as Croton cali- 

 fornicuSj Croton setigerus, and Aselepias erosa. 



The differences in vegetation between the foothill belt and the 

 plains appear to be caused, however, largely by habitat and not to be 

 the signs of a true zonal demarkation. 



'"The word 'intramontane' is applied to that portion of California west of aline 

 of mountains made up of the Sierra Nevada, San Bernardino, and San Jacinto ranges, 

 together with their connecting ridges. That area is thus distinguished from the 

 ultramontane or desert and Great Basin portions of the State. The two regions are 

 marked by distinct characteristic floras. North of the Sierra Nevada and south of 

 the San Jacinto Mountains the precise location of the dividing line has not been 

 clearly determined." Coville, Proceedings of the Biological Society of Washington, 

 Vol. vii, p. 80 (1892). 



