Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Factors affecting vegeation on a serpentine soil. II. Chemical composition of foliage and soil.

Abstract

Ion concentrations in the foliage of Adenostoma fasciculatum, Arctostaphylos viscida, Cupressus sargentii, and Quercus durata were determined and correlated with the abundance and plant size of these indigenous species and with soil concentrations of these ions. The species differed most in Ca concentration, and only slightly in K concentration. In all species the accumulation ratios were greater for K (meq/100 g in plant/meq 100 g in soil) than for any other element; the next highest was for Ca. The accumulation ratio for Mg exceeded 1.0 only in Adenostoma fasciculatum. This species occurred mostly on soils with a relatively high Ca content, had the lowest Ca concentration in its leaves, was most abundant where Ca concentration in its leaves was highest, and had the highest Mg accumulation ratio. These facts indicate that this species is least adapted to serpentine conditions. Cupressus sargentii was well-adapted to the conditions found in this study. This species accumulated Ca and excluded Mg resulting in an average Ca/Mg ratio in its leaves of 1.44, while the soil it grew on had an average Ca/Mg ratio of 0.08. Percentage cover and density of Arctostaphylos viscida were the only variables to be correlated negatively with Ca or Ca/Mg ratio. This seems to indicate that A. viscida has low optima for Ca and the Ca/Mg ratio. There was no evidence of toxicity of Ni, Cr, or Co. Molybdenum concentrations in leaf tissue were below detectable limits (0.2 ppm). Introduced species should have a better chance for success on the sites supporting non-cypress stands, and their chances within these sites should be best where Adenostoma fasciculatum and Garrya congdoni are most abundant because of the more favorable Ca status of the soil supporting them.