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.

"thick" is not a number.

... more about "Erigeron subtrinervis"
not tailed +, rounded +  and obtuse +
distinct +
subequal +
scarious +
usually triangular +  and linear +
usually deltate +  and lanceolate +
indeterminate +  and determinate +
Guy L. Nesom +
Rydberg ex Porter & Britton +
2 cm20 mm <br />0.02 m <br /> (2.7 cm27 mm <br />0.027 m <br />) +
3 cm30 mm <br />0.03 m <br /> (8 cm80 mm <br />0.08 m <br />) +
oblanceolate-spatulate +
0.6 cm6 mm <br />0.006 m <br /> (2 cm20 mm <br />0.02 m <br />) +
decurrent +
Erigeron glabellus var. mollis +
linear;lanceolate oblanceolate or spatulate +
rugulose +  and muricate +
lanceolate +  and oblong oblong-ovate or broadly ovate +
largest +  and equal-sized +
not 2-lipped +  and actinomorphic +
blue +  and lavender +
0.7 cm7 mm <br />0.007 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
beaked +, 2-ribbed +  and 5-ribbed +
subterete +, oblong +  and oblong-obovoid compressed +
fertile +  and bisexual +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
fertile +  and bisexual +
Colo. +, Idaho +, Mont. +, Nebr. +, N.Mex. +, N.Dak. +, S.Dak. +, Utah +  and Wyo. +
1800–3000(–3500) m +
strigose +, evenly hirsute +  and strigoso-hirsute +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Opening and margins, roadsides, often shaded, ponderosa pine, pine-fir, mixed conifer, aspen +
disciform +  and discoid +
in loose , corymbiform or paniculiform arrays +  and singly +
indeterminate +
heterogamous +  and homogamous +
each +  and sessile +
0.5 cm5 mm <br />0.005 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
0.6 cm6 mm <br />0.006 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
turbinate;hemispheric +
1.3 cm13 mm <br />0.013 m <br /> (2 cm20 mm <br />0.02 m <br />) +
petiolate +  and sessile +
cauline +  and basal +
erect;spreading +
deltate +
Not (?) +  and Scarious (?) +
2-carpellate +
Flowering (Jun–)Jul–Sep. +
3-nerved +  and 1-nerved +
narrowly elliptic +  and linear-lanceolate +
Mem. Torrey Bot. Club +
bearing subulate enations +, hairy +  and bristly +
exalbuminous +
prostrate +  and decumbent +
appendaged +  and truncate +
papillate +  and smooth +
Erigeron speciosus var. mollis +
Erigeron subtrinervis +
Erigeron +
species +
inflated +  and tubular +
fibrous-rooted +, rhizomatous +  and subrhizomatous +
90 cm900 mm <br />0.9 m <br /> (100 cm1,000 mm <br />1 m <br />) +
15 cm150 mm <br />0.15 m <br /> (90 cm900 mm <br />0.9 m <br />) +
tree +, shrub +  and subshrub +