Publication: Brittonia 11(3): 120-121, f. 1D, 3-4. 1959.
selected vouchers: WTU
Notes: Dempster and Ehrendorfer (1965) recognized 9 subspecies in their treatment of this species. They list several of these subspecies as occurring in Washington, the majority of which are parapatric to one or more of each other. Until further research is conducted on the distinctiveness of these infraspecific taxa, we will recognize G. serpenticum at the species level only.
Dempster and Ehrendorfer: "The name G. serpenticum circumscribes a rather polymorphic assemblage of diploid and some tetraploid races having many characters in common and often so tightly connected by transitional forms that further specific subdivision seems impossible....It is possible that the pattern here outlined may be the result of primary geographical and ecological differentiation which has become blurred by secondary hybridizations. The disjunct group of western montane races may represent the remnants of an older, more grayanum-like northward push along the Cascades, which has become fractionated and more or less strongly infiltrated by eastern and central races during times of dryer and more continental climate."