Chaffless or dwarf saw-wort

Saussurea alpina (Linnaeus) de Candolle; S. alpina var. ledebourii A. Gray; S. densa (Hooker) Rydberg; S. nuda subsp. densa (Hooker) G. W. Douglas; S. nuda var. densa (Hooker) Hultén

Plants 5–60 cm; branched caudices; herbage subglabrous to loosely tomentose when young, ± glabrescent, at least proximally. Stems usually simple. Leaves basal and cauline ± smaller distally, tapered to winged petioles to 7 cm, blades elliptic or lanceolate to ovate, 5–15 cm, bases obtuse to acute, margins subentire to sinuate, dentate or denticulate, apices acute to acuminate; distal cauline sessile, ± decurrent. Heads 3–20+ in corymbiform to subcapitate arrays; (peduncles 0–5 cm. . Involucres 10–15 mm. Phyllaries in 3–4 series subequal or weakly imbricate, linear to lanceolate, abaxial faces dark green, often tinged dark purplish, loosely villous or ± tomentose. Receptacles naked. Florets 15–20; corollas purple, 8–11 mm, tubes 4–6 mm, throats 1.5–2 mm, lobes 3–3.5 mm; anthers dark purple. Cypselae stramineous, 6–7 mm; pappi of white to brownish, outer bristles 1–3 mm, inner 9–10 mm. 2n = 26 (as S. densa).

Flowering Jun–Aug. Coastal dunes, estuaries, alpine tundra; 0–100, 2000–2800 m; Alta.; B.C.; Alaska, Mont.; Russian Far East.

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.