Largeflower Fleabane

Erigeron hultenii S. A. Spongberg was noted to be "closely allied to the polymorphic arctic-alpine species E. grandiflorus W. J. Hooker" (S. A. Spongberg 1973, p. 116) and to have a "close morphologic resemblance to some plants of E. grandiflorus from Alaska" [E. porsildii in the present sense] (p. 119). Plants corresponding to E. hultenii have not been recollected, and that taxon does not fit with any other known Alaskan species. Contrasts with E. porsildii exclude it from that species. Erigeron hultenii is not recognized formally herein.

Perennials, (2–)10–20(–25) cm; rhizomatous, fibrous-rooted, rhizomes horizontal or erect, sometimes branched, relatively short, sometimes resembling taproots. Stems erect, sparsely to moderately villous (hairs 0.5–1.6 mm), usually stipitate-glandular (hairs 0.05–0.4 mm). Leaves basal (persistent) and cauline; basal blades oblong-oblanceolate to narrowly obovate, 30–120 × (3–)5–14 mm, margins entire (apices acute), faces densely hirsute to coarsely villous, sparsely stipitate-glandular to minutely glandular; cauline blades oblong-lanceolate to lanceolate, gradually reduced distally or nearly equal-sized (bases often subclasping). Heads 1. Involucres 6–10 × 12–20 mm. Phyllaries in ca. 2 series (purple at least at tips, narrowly lanceolate, equal, apically acuminate), densely hirsute, hirsuto-villous, or villous (hairs whitish, cross walls not colored), sparsely stipitate-glandular to minutely glandular. Ray florets 65–110; corollas white to lavender or blue, 13–17 mm (1.2–1.7 mm wide), laminae weakly coiling. Disc corollas 3.8–4.5 mm. Cypselae 2–2.5 mm, 2-nerved, faces sparsely strigose; pappi: outer of relatively long setae or scales, inner of 14–20(–25) bristles. 2n = 36.

Erigeron grandiflorus Hooker subsp. arcticus A. E. Porsild, Publ. Bot. (Ottawa) 4: 67. 1975, not E. arcticus Rouy 1903

Erigeron porsildii is an Arctic species of flowering plant in the family Asteraceae known by the common name Porsild's Arctic fleabane. It has been found in Alaska, Yukon, and the Northwest Territories.

Erigeron porsildii is a perennial herb up to 25 centimeters (10 inches) tall, spreading by means of underground rhizomes. Leaves and stems are covered with many hairs The plant generally produces only one flower head per stem. Each head has 65–110 blue, lavender, or white ray florets surrounding numerous yellow disc florets. The species grows on cliffs, talus, gravel, and dry tundra.