A Study of Morphological Variability in Chenopodium incanum (Chenopodiaceae) and the Recognition of Two New Varieties

Abstract

Study ofChenopodium incanum has revealed considerable variability in what has been viewed previously as a uniform species. Variation is correlated with geographic distribution, and thus two new varieties are described. Varietyeatum Crawford occurs in western Texas, southern New Mexico and southern Arizona, whereas var.occidentale Crawford is restricted to the Great Basin and Mohave Desert. The var.incanum grows primarily on the western Great Plains and eastern slopes of the Rocky Mountains. Morphological features serving to distinguish the varieties are presented and discussed. Also considered are the characters that allow the separation ofC. incanum andC. fremontii.