Erigeron subtrinervis

Rydberg ex Porter & Britton

Mem. Torrey Bot. Club 5: 328. 1894.

Endemic
Basionym: Erigeron glabellus var. mollis A. Gray Proc. Acad. Nat. Sci. Philadelphia 15: 64. 1864,
Synonyms: Erigeron speciosus var. mollis (A. Gray) S. L. Welsh
Treatment appears in FNA Volume 20. Treatment on page 330. Mentioned on page 269, 331.

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: Flowering (Jun–)Jul–Sep.
Habitat: Opening and margins, roadsides, often shaded, ponderosa pine, pine-fir, mixed conifer, aspen
Elevation: 1800–3000(–3500) m

Distribution

V20-750-distribution-map.gif

Colo., Idaho, Mont., Nebr., N.Mex., N.Dak., S.Dak., Utah, 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.

Selected References

None.

Lower Taxa

None.
... more about "Erigeron subtrinervis"
Guy L. Nesom +
Rydberg ex Porter & Britton +
Erigeron glabellus var. mollis +
Colo. +, Idaho +, Mont. +, Nebr. +, N.Mex. +, N.Dak. +, S.Dak. +, Utah +  and Wyo. +
1800–3000(–3500) m +
Opening and margins, roadsides, often shaded, ponderosa pine, pine-fir, mixed conifer, aspen +
Flowering (Jun–)Jul–Sep. +
Mem. Torrey Bot. Club +
Erigeron speciosus var. mollis +
Erigeron subtrinervis +
Erigeron +
species +