Pedicularis oederi

Vahl ex Hornemann

Fors. Oecon. Plantel. ed. 2, 580. 1806.

Common names: Oeder’s lousewort
Synonyms: Pedicularis oederi var. albertae (Hultén) B. Boivin
Treatment appears in FNA Volume 17. Treatment on page 526. Mentioned on page 513, 518, 522.

Plants 2–15 cm. Leaves: basal 2–10, blade lanceolate, 10–70 x 3–15 mm, 1-pinnatifid, margins of adjacent lobes nonoverlapping or extensively overlapping distally, 2-serrate, surfaces glabrous or slightly tomentose; cauline 1–5, blade lanceolate, 15–50 x 3–20 mm, 1-pinnatifid, margins of adjacent lobes nonoverlapping or extensively overlapping distally, 1- or 2-serrate, surfaces glabrous or slightly tomentose. Racemes simple, 1 or 2, exceeding basal leaves, each 10–50-flowered; bracts linear to lanceolate, 5–20 x 1–2 mm, undivided or 1-pinnatifid, proximal margins entire, distal serrate, surfaces glabrous or tomentose. Pedicels 2–5 mm. Flowers: calyx 8–11 mm, tomentose, lobes 5, triangular, 1–3 mm, apex entire or serrate, glabrous, sometimes ciliate; corolla 15–24 mm, tube yellow, 9–15 mm; galea bicolored, yellow proximally, brown or red distally, 6–9 mm, beakless, margins entire medially and distally, apex arching slightly over abaxial lip; abaxial lip yellow, 4–5 mm. 2n = 16 (Asia).

Phenology: Flowering Jun–Aug.
Habitat: Arctic and alpine tundras.
Elevation: 500–3700 m.


Alta., B.C., N.W.T., Yukon, Alaska, Mont., Wyo., Eurasia.


Pedicularis oederi is known from the mountains of Europe, Asia, and western North America.

Two arctic species can be easily confused with Pedicularis oederi. Pedicularis flammea also has bicolored flowers that are yellow with galeas that are red- or purple-tipped, but the flowers of P. oederi are twice the size of those of P. flammea. The flowers of P. capitata are sometimes also yellow but may or may not be bicolored. If bicolored, the color is more diffuse and lighter than that of either P. flammea or P. oederi. The flowers of P. capitata are also larger than those of P. oederi. In addition, the inflorescences of P. capitata usually have no more than five flowers clustered at the tips, while those of P. oederi have at least 10 to 50 flowers along at least one third their lengths. H. J. Scoggan (1978–1979) listed P. oederi var. albertae based upon its densely woolly inflorescence.

Selected References


Lower Taxa

... more about "Pedicularis oederi"
Bruce W. Robart +
Vahl ex Hornemann +
Oeder’s lousewort +
Alta. +, B.C. +, N.W.T. +, Yukon +, Alaska +, Mont. +, Wyo. +  and Eurasia. +
500–3700 m. +
Arctic and alpine tundras. +
Flowering Jun–Aug. +
Fors. Oecon. Plantel. ed. +
Pedicularis oederi var. albertae +
Pedicularis oederi +
Pedicularis +
species +