Petasites frigidus var. frigidus
Basal leaves: blades palmately nerved, sagittate, deltate, or reniform to cordate, 2–25 × 2–27 cm, margins lobed (primary lobes 0–14, entire or dentate, secondary lobes 0–25, entire or irregularly toothed, lobed, or deeply parted, in extreme forms lobes with at least 2 lateral triangular teeth, lobes often overlapping, sinuses oblong and closed) or not lobed (dentate, teeth to 22 per side), abaxial faces floccose to woolly, adaxial faces mostly glabrous or sparsely tomentulose. Staminate heads 2–20; ray-florets 1–13, corolla laminae 1.6–12 mm; disc-floret style-branches 0.05–2 mm, papillate or hairy. Pistillate heads 5–19; ray-florets 30–109, corolla laminae 0.8–4.8 mm; disc-florets: corolla lobes 0.4–4.4 mm, style-branches 0–1.2 mm, papillate or hairy. Pappi (pistillate) to 15 mm. 2n = ca. 60, 90.
Phenology: Flowering early spring.
Habitat: Arctic tundra, moist alpine-subalpine slopes, streams, marshes, edges of moist forests, gravelly or sandy roadsides
Elevation: 10–2300 m
Alta., B.C., N.W.T., Nunavut, Sask., Yukon, Alaska, Oreg., Wash., n Eurasia