THE BROAD-SCLEROPHYLL VEGETATION OF CALIFORNIA. 



33 



The original vegetation still remaining is comprised in several 

 large patches, the two principal ones being at the northwest and 

 southeast extremities of the ridge. It is true that these are mere 

 remnants, but they are of sufficient size to show absolutely natural 

 conditions, except along the edges. The studies were made in the 

 area at the southeast extremity, which covers approximately 2.5 

 sq. km. and includes the highest point of the ridge. It possesses 

 rather bold relief, including several summits and ravines, one of 

 which is decidedly abrupt. The extreme range of altitude is from 

 184 meters at the bottom of the deepest ravine to 246 meters at 



Fig. 2. — Quadrat at station 1, 5 meters square Note abundance 

 of individuals of Adenostoma, which, however, are 

 small and do not control the area. For symbols in 

 this and succeeding quadrats see footnote, p. 34. 



the highest hilltop. The vegetation of the area is mainly chaparral. 

 The Adenostoma consociation covers the south-facing slopes and the 

 summits and is by far the most extensive type; Arctostaphylos is 

 dominant upon the gentler north-facing slopes; and on the north- 

 facing slope of the deepest ravine is a typical area of the Quercus 

 agrifolia- Arbutus association of the broad-sclerophyll forest. It is 

 thus an ideal place in which to study the various communities of 

 broad-sclerophyll vegetation and their relations to habitat and to 

 each other. 



For quadrat and instrumental study a series of ten stations was 

 determined upon, lying on an approximately north-south line 



