Erigeron davisii

(Cronquist) G. L. Nesom

Sida 21: 22. 2004.

Common names: Davis’s fleabane
EndemicConservation concern
Basionym: Erigeron engelmannii subsp. davisii Cronquist Leafl. W. Bot. 3: 167. 1942 (as engelmanni)
Synonyms: Erigeron engelmannii var. davisii (Cronquist) Cronquist
Treatment appears in FNA Volume 20. Treatment on page 287. Mentioned on page 259, 270, 271.

Perennials, 10–30 cm; taprooted, caudices simple or with relatively short, thick branches. Stems erect, hirsuto-villous to loosely strigose (hairs relatively translucent and vitreous, unequal in lengths, 0.1–1 mm), sometimes sparsely minutely glandular. Leaves mostly basal (persistent; petioles prominently ciliate, hairs spreading, thick-based), eglandular; blades linear to narrowly oblanceolate, 20–100 × 1–3.5 mm, abruptly reduced distally, margins entire, faces strigose to strigoso-hirsute, eglandular. Heads 1. Involucres 5–8 × 10–15 mm. Phyllaries in 2–3 series, loosely hirsute to hirsuto-villous, sometimes sparsely minutely glandular. Ray-florets 50–80; corollas usually white, 8–14 mm, laminae (1.2–1.8 mm wide) coiling. Disc corollas 3.1–4 mm (glabrate, throats not indurate or inflated). Cypselae (obovoid) 2.1–2.5 mm, 2-nerved, faces sparsely to moderately strigoso-villous; pappi: outer of setae, inner of 14–20 bristles.


Phenology: Flowering (Apr–)May–Jul.
Habitat: Bare, rocky ridges and slopes, basalt outcrops, sparsely vegetated woodland openings or edges, commonly with grasses
Elevation: 1200–1800 m

Discussion

Of conservation concern.

Selected References

None.

Lower Taxa

None.
... more about "Erigeron davisii"
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 +
(Cronquist) G. L. Nesom +
decurrent +
Erigeron engelmannii subsp. davisii +
2 cm20 mm <br />0.02 m <br /> (10 cm100 mm <br />0.1 m <br />) +
linear;narrowly oblanceolate +
reduced +
1mm;3.5mm +
rugulose +  and muricate +
with relatively short , thick branches +  and simple +
Davis’s fleabane +
not 2-lipped +  and actinomorphic +
0.8 cm8 mm <br />0.008 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
beaked +, 2-ribbed +  and 5-ribbed +
subterete +, oblong +  and oblong-obovoid compressed +
fertile +  and bisexual +
0.31 cm3.1 mm <br />0.0031 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
fertile +  and bisexual +
Idaho +  and Oreg. +
1200–1800 m +
strigoso-villous +, strigose +  and strigoso-hirsute +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Bare, rocky ridges and slopes, basalt outcrops, sparsely vegetated woodland openings or edges, commonly with grasses +
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 />) +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
turbinate;hemispheric +
1 cm10 mm <br />0.01 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
erect;spreading +
deltate +
Not (?) +  and Scarious (?) +
2-carpellate +
Flowering (Apr–)May–Jul. +
3-nerved +  and 1-nerved +
loosely hirsute +  and hirsuto-villous +
narrowly elliptic +  and linear-lanceolate +
bearing subulate enations +, hairy +  and bristly +
exalbuminous +
Endemic +  and Conservation concern +
branched +  and simple +
prostrate +  and decumbent +
appendaged +  and truncate +
papillate +  and smooth +
Erigeron engelmannii var. davisii +
Erigeron davisii +
Erigeron +
species +
inflated +  and tubular +
90 cm900 mm <br />0.9 m <br /> (100 cm1,000 mm <br />1 m <br />) +
10 cm100 mm <br />0.1 m <br /> (30 cm300 mm <br />0.3 m <br />) +
tree +, shrub +  and subshrub +