North American populations of
Saussurea nuda occur in two distinctly different sets of habitats. Plants from coastal Alaska have been recognized as var.
nuda and dwarfed alpine plants from the northern Rockies as var.
densa. According to E. Hultén (1941–1950, vol. 10), the only differences between var.
densa and var.
nuda are the "more densely denticulated leaves and very congested inflorescences" of the former. Notwithstanding the very different habitats, some coastal Alaskan specimens [e.g.,
Ward 53 (ALA)] are indistinguishable from the alpine forms. In Siberia,
S. nuda is a polymorphic species occurring from coastal sites to alpine areas (S. J. Lipschitz 1979).
Saussurea ×tschuktschorum Lipschitz is apparently a hybrid between S. angustifolia and S. nuda. It resembles S. angustifolia; it has naked receptacles like S. nuda.