An analysis of morphological variation in Muhlenbergia capillaris (Poaceae) and its allies in the southeastern United States

Muhlenbergia capillaris and its allied species, M. expansa and M. filipes have been variously classified in the past as three distinct species or a single species with three varieties. A numerical analysis was performed on data taken from herbarium specimens collected throughout the geographic distribution of these taxa. Analysis of variance, principal components analysis, cluster analysis, and discriminate analysis indicate there is a continuum of morphological variation present. A single species with three varieties (var. capillaris var. filipes and var. trichopodes is recognized. A key to the varieties and descriptions of each are presented.