< Back to the Object

Edit History
Erigeron subtrinervis Rydberg ex Porter & Britton [family COMPOSITAE]

Date Updated: 23 July 2012

Herbarium
Flora of North America (FNA)
Collection
Flora of North America
Resource Type
Reference Sources
Entry From
Flora of North America, Vol 20,
Names
Erigeron subtrinervis Rydberg ex Porter & Britton [family COMPOSITAE], Mem. Torrey Bot. Club, 5: 328. 1894 Erigeron glabellus Nuttall var. mollis A. Gray [family COMPOSITAE], Proc. Acad. Nat. Sci. Philadelphia, 15: 64. 1864,. not E. mollis D. Don 1825 Erigeron speciosus (Lindley) de Candolle var. mollis (A. Gray) S. L. Welsh [family COMPOSITAE]
Treatment Author(s)
Guy L. Nesom
Information
Perennials, 15–90 cm; rhizomatous to subrhizomatous, fibrous-rooted, caudices usually branched, woody, thick. Stems erect, moderately to densely hirsute (hairs 0.5–0.8 mm), eglandular. Leaves basal (usually withering by flowering) and cauline; basal blades oblanceolate-spatulate, 30–80 × 6–20(–27) mm, margins entire, faces evenly hirsute to strigoso-hirsute, usually eglandular; cauline blades lanceolate to oblong, oblong-ovate, or broadly ovate, nearly even-sized distally or sometimes mid largest (continuing to immediately proximal to heads, bases clasping to subclasping). Heads 1–6(–21) in corymbiform arrays. Involucres 6–9 × 13–20 mm. Phyllaries in 2–3(–4) series, moderately to densely hirsute, minutely glandular. Ray florets 100–150; corollas blue to lavender, 7–18 mm (ca. 1 mm wide), laminae coiling at tips. Disc corollas 4–5 mm. Cypselae 1.6–2 mm, 2(–4)-nerved, faces sparsely strigose; pappi: outer of setae, inner of 20–30 bristles.
Phenology
jun-aug (summer), sep (fall)
Altitude range
1800–3000(–3500) m;
Distribution
USA Colo.USA IdahoUSA Mont.USA Nebr.USA N.Mex.USA N.Dak.USA S.Dak.USA UtahUSA Wyo.
Discussion
Erigeron subtrinervis is variable in vestiture, perhaps reflecting gene exchange with E. speciosus. Erigeron speciosus var. mollis (A. Gray) S. L. Welsh may be a recurrent hybrid; it is identified here within E. subtrinervis.

Date Updated: 23 July 2012

Herbarium
Flora of North America (FNA)
Collection
Flora of North America
Resource Type
Reference Sources
Entry From
Flora of North America, Vol 20,
Names
Erigeron subtrinervis Rydberg ex Porter & Britton [family COMPOSITAE], Mem. Torrey Bot. Club, 5: 328. 1894 Erigeron glabellus Nuttall var. mollis A. Gray [family COMPOSITAE], Proc. Acad. Nat. Sci. Philadelphia, 15: 64. 1864,. not E. mollis D. Don 1825 Erigeron speciosus (Lindley) de Candolle var. mollis (A. Gray) S. L. Welsh [family COMPOSITAE]
Treatment Author(s)
Guy L. Nesom
Information
Perennials, 15–90 cm; rhizomatous to subrhizomatous, fibrous-rooted, caudices usually branched, woody, thick. Stems erect, moderately to densely hirsute (hairs 0.5–0.8 mm), eglandular. Leaves basal (usually withering by flowering) and cauline; basal blades oblanceolate-spatulate, 30–80 × 6–20(–27) mm, margins entire, faces evenly hirsute to strigoso-hirsute, usually eglandular; cauline blades lanceolate to oblong, oblong-ovate, or broadly ovate, nearly even-sized distally or sometimes mid largest (continuing to immediately proximal to heads, bases clasping to subclasping). Heads 1–6(–21) in corymbiform arrays. Involucres 6–9 × 13–20 mm. Phyllaries in 2–3(–4) series, moderately to densely hirsute, minutely glandular. Ray florets 100–150; corollas blue to lavender, 7–18 mm (ca. 1 mm wide), laminae coiling at tips. Disc corollas 4–5 mm. Cypselae 1.6–2 mm, 2(–4)-nerved, faces sparsely strigose; pappi: outer of setae, inner of 20–30 bristles.
Phenology
jun-aug (summer), sep (fall)
Altitude range
1800–3000(–3500) m;
Distribution
USA Colo.USA IdahoUSA Mont.USA Nebr.USA N.Mex.USA N.Dak.USA S.Dak.USA UtahUSA Wyo.
Discussion
Erigeron subtrinervis is variable in vestiture, perhaps reflecting gene exchange with E. speciosus. Erigeron speciosus var. mollis (A. Gray) S. L. Welsh may be a recurrent hybrid; it is identified here within E. subtrinervis.
Erigeron subtrinervis Rydberg ex Porter & Britton [family COMPOSITAE]
PDF

Related Materials