Factors affecting vegetation on a serpentine soil. I. Principal component analysis of vegetation data.

Abstract

Stands with Cupressus sargentii also contained Arctostaphylos viscida and occurred on mesic sites with lower Ca in the sub- surface soil. Stands without C. sargentii usually contained Adenostoma fasciculatum and Quercus durata and occurred on drier sites with higher Ca. A moisture gradient within the cypress stands was associated mainly with the water-storage capacity of the soil. Cupressus sargentii was more abundant at lower water-storage capacities (and at lower elevations), while Arctostaphylos viscida was most abundant at the opposite end of the gradient. Adenostoma fasciculatum and Garrya congdoni were most abundant where Ca contents in the the soil were high while Ceanothus jepsonii, Q. durata, Bromus laevipes, and Sisyrinchium bellum were most abundant at the opposite end of the gradient.-from Authors