Influence of Soil Type on the Distribution of Two Closely Related Species of Erigeron

On soils derived from a uniform bedrock two closely related species of Erigeron replace each other elevationally in the White Mountains of California. Populations of the two species occur side—by—side at places at the same elevation but on dissimilar soils because of compensations provided by the interactions of substrate color, temperature, moisture, and chemistry. The altitudinal distribution of the species is controlled by temperature at the upper limits and moisture at the lower. See full-text article at JSTOR