Wyethia amplexicaulis

(Nuttall) Nuttall

Trans. Amer. Philos. Soc., n. s. 7: 352. 1840.

Basionym: Espeletia amplexicaulis Nuttall J. Acad. Nat. Sci. Philadelphia 7: 38. 1834
Synonyms: Wyethia amplexicaulis subsp. major Piper Wyethia amplexicaulis subsp. subresinosa Piper Wyethia lanceolata
Treatment appears in FNA Volume 21. Treatment on page 102. Mentioned on page 101, 103, 104.

Plants 25–50(–100) cm. Basal leaves: blades (green, shining) lance-elliptic or oblong-lanceolate to lanceolate, 15–30(–40+) cm, margins usually entire, sometimes denticulate or dentate, not ciliate, faces glabrous (gland-dotted, vernicose); cauline leaves similar, smaller distally (distalmost sessile, usually ± clasping). Heads usually 2–8 in ± corymbiform to racemiform arrays, sometimes borne singly. Involucres hemispheric to turbinate, 15–30 mm diam. Phyllaries 18–36+, subequal or unequal, herbaceous (at least outer), margins not ciliate, faces glabrous; outer 18–32 mm (surpassing inner). Ray florets 8–21(–25); laminae 25–60 mm. Cypselae 8–9 mm, glabrous. 2n = 38.

Phenology: Flowering May–Jul.
Habitat: Wet to dry, open sites, meadows, sagebrush scrub, yellow-pine forests
Elevation: 400–3000 m



Colo., Idaho, Mont., Nev., Oreg., Utah, Wash., Wyo.


Wyethia amplexicaulis introgressively hybridizes with W. arizonica (producing plants called W. ×magna A. Nelson ex W. A. Weber) across a broad area of central and southern Colorado. Habit of the hybrid is typical of W. amplexicaulis; the indument resembles that of W. arizonica in varying degrees. Occasionally, W. amplexicaulis hybridizes with but does not introgress with W. helianthoides.

Selected References


Lower Taxa

... more about "Wyethia amplexicaulis"
William A. Weber +
(Nuttall) Nuttall +
Espeletia amplexicaulis +
Colo. +, Idaho +, Mont. +, Nev. +, Oreg. +, Utah +, Wash. +  and Wyo. +
400–3000 m +
Wet to dry, open sites, meadows, sagebrush scrub, yellow-pine forests +
Flowering May–Jul. +
Trans. Amer. Philos. Soc., n. s. +
Illustrated +  and Endemic +
Wyethia amplexicaulis subsp. major +, Wyethia amplexicaulis subsp. subresinosa +  and Wyethia lanceolata +
Wyethia amplexicaulis +
species +