Erigeron denalii

A. Nelson

Amer. J. Bot. 32: 289. 1945.

Common names: Denali fleabane
Endemic
Synonyms: Erigeron mexiae K. M. Becker Erigeron purpuratus var. dilatatus B. Boivin
Treatment appears in FNA Volume 20. Treatment on page 303. Mentioned on page 265.

Perennials, 1–5 cm; taprooted, caudices diffuse with extensive systems of rhizomelike, relatively long and slender branches. Stems erect (simple, ± scapiform), villous, granular-glandular. Leaves basal (persistent) and cauline; blades spatulate to oblanceolate-spatulate, 10–20 × 2–4 (–5) mm, mid larger than basal and proximal, margins entire or shallowly (2–) 3-lobed or toothed apically (apices obtuse to nearly truncate), faces moderately villous, minutely glandular. Heads 1. Involucres (4–) 5–7 × 9–12 mm. Phyllaries in 2 (–3) series, densely lanate-villous (hairs to 3 mm, often with dark purple cross-walls), glandular. Ray-florets 30–55; corollas white to lavender, 4–8 mm, laminae (filiform to narrowly straplike, 0.3–2 mm wide, often involute) erect, rarely spreading, not coiling or reflexing. Disc-florets 3.8–4.8 mm. Cypselae 3–3.8 mm, 2-nerved, faces strigillose to strigoso-hirsute; pappi: outer 0 (or inconspicuous), inner of 20–25 (usually ± purple-red tinged, sometimes whitish, variable within populations) bristles.


Phenology: Flowering Jun–Aug.
Habitat: Open alpine and subalpine habitats, tundra slopes, openings in spruce-fir woods, gravelly and shaley scree, cut banks
Elevation: 900–2200 m

Distribution

V20-650-distribution-map.gif

B.C., N.W.T., Yukon, Alaska.

Discussion

Erigeron denalii and E. purpuratus are similar and probably closely related; the two appear to be partially sympatric; differences in vestiture and leaf morphology are constant. The habitat of E. purpuratus, sandy or gravelly alluvium, also is remarkably constant and distinct from that of E. denalii. Apparently correlated with the habitat, plants of E. purpuratus almost always develop a relatively long and slender, woody taproot; taproots of E. denalii apparently are less well defined and often are not collected.

Plants of the type collection of Erigeron mexiae have ray corollas with relatively broad laminae (1.5–2 mm wide); ray corolla width is variable in E. denalii, and E. mexiae is regarded here as an extreme variant within the species. In other characters, there appears to be no difference.

Selected References

None.

Lower Taxa

None.
... more about "Erigeron denalii"
not tailed +, rounded +  and obtuse +
distinct +
subequal +
scarious +
usually triangular +  and linear +
usually deltate +  and lanceolate +
paniculiform +, corymbiform +  and loose +
indeterminate +  and determinate +
Guy L. Nesom +
A. Nelson +
decurrent +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
proximal +  and mid +
spatulate;oblanceolate-spatulate +
2mm;4mm +
rugulose +  and muricate +
Denali fleabane +
not 2-lipped +  and actinomorphic +
white +  and lavender +
0.4 cm4 mm <br />0.004 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
beaked +, 2-ribbed +  and 5-ribbed +
subterete +, oblong +  and oblong-obovoid compressed +
0.38 cm3.8 mm <br />0.0038 m <br /> (0.48 cm4.8 mm <br />0.0048 m <br />) +
fertile +  and bisexual +
fertile +  and bisexual +
B.C. +, N.W.T. +, Yukon +  and Alaska. +
900–2200 m +
strigillose +  and strigoso-hirsute +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Open alpine and subalpine habitats, tundra slopes, openings in spruce-fir woods, gravelly and shaley scree, cut banks +
disciform +  and discoid +
in loose , corymbiform or paniculiform arrays +  and singly +
indeterminate +
heterogamous +  and homogamous +
each +  and sessile +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
turbinate;hemispheric +
0.9 cm9 mm <br />0.009 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
reflexing +, spreading +  and erect +
not coiling +
petiolate +  and sessile +
cauline +  and basal +
erect;spreading +
deltate +
more or less dentate to pinnatifid +  and entire +
toothed +, (2-)3-lobed +  and entire +
Not (?) +  and Scarious (?) +
2-carpellate +
Flowering Jun–Aug. +
3-nerved +  and 1-nerved +
lanate-villous +
narrowly elliptic +  and linear-lanceolate +
Amer. J. Bot. +
bearing subulate enations +, hairy +  and bristly +
exalbuminous +
branched +  and simple +
prostrate +  and decumbent +
appendaged +  and truncate +
papillate +  and smooth +
Erigeron mexiae +  and Erigeron purpuratus var. dilatatus +
extensive +
Erigeron denalii +
Erigeron +
species +
inflated +  and tubular +
90 cm900 mm <br />0.9 m <br /> (100 cm1,000 mm <br />1 m <br />) +
1 cm10 mm <br />0.01 m <br /> (5 cm50 mm <br />0.05 m <br />) +
tree +, shrub +  and subshrub +