Agoseris ×elata

(Nuttall) Greene

Pittonia 2: 177. 1891.

Common names: Willamette agoseris
Basionym: Stylopappus elatus Nuttall Trans. Amer. Philos. Soc., n. s. 7: 433. 1841
Synonyms: Agoseris grandiflora var. laciniata (Nuttall) Jepson Agoseris laciniata (Nuttall) Greene Agoseris tenuifolia Rydberg Stylopappus laciniatus Nuttall Stylopappus laciniatus var. longifolius Nuttall Troximon grandiflorum var. laciniatum (Nuttall) A. Gray Troximon grandiflorum var. tenuifolium A. Gray Troximon nuttallii
Treatment appears in FNA Volume 19. Treatment on page 334. Mentioned on page 324, 325, 330.
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Stems 0. Leaves erect to ascending; blades usually oblanceolate, sometimes lanceolate or obovate, 15–25 cm, margins usually toothed to lobed or pinnatifid, rarely entire, lobes 2–4 pairs, lanceolate to triangular, antrorse to spreading, lobules mostly 0, faces glabrous and glaucous or sparsely villous. Peduncles ± elongating after flowering, 15–65 (–90) cm in fruit, glabrate, or apically pubescent or villous, ± stipitate-glandular. Involucres obconic to campanulate, 2–4 cm in fruit. Phyllaries in 2–4 series, medially rosy purple, sometimes purple-black apically, rarely all green or purple-black spotted, faces pubescent to villous, ± stipitate-glandular; outer mostly spreading, adaxially ± villous and eglandular; inner erect, elongating after flowering. Receptacles epaleate. Florets (25–) 50–150; corollas orange or yellow, tubes 8–10 mm, ligules 6–8 (–12) × 1–3 mm; anthers 2–3 (–5) mm. Cypselae (11–) 14–20 mm, bodies ± fusiform, (6–) 8–10 mm, beaks 5–10 mm, mostly equaling bodies; ribs broadly ridged, straight; pappus bristles in 2–3 series, 10–14 mm.


Phenology: Flowering Jun–Sep.
Habitat: Lowland prairies
Elevation: 10–100 m

Distribution

V19-515-distribution-map.gif

Oreg., Wash., and montane meadows or open pine forests, 1400–2800 m, Calif., Oreg., Wash.

Discussion

Agoseris ×elata has been and continues to be an enigmatic taxon. Perhaps no other name in the genus has been so misunderstood and misapplied. Many herbarium specimens labeled A. ×elata are in fact misidentified. Specimens of A. ×elata are not abundant in herbaria; the number of actual collections is relatively small compared to those for other Agoseris. Specimens that belong to A. ×elata represent a complex assemblage that has relatively few defining features and appears to be of hybrid origin. Most specimens appear to be intermediate between A. grandiflora and A. aurantiaca; most also appear to have characteristics of A. monticola or A. glauca var. dasycephala. The exact parentage remains unclear.

Agoseris ×elata occurs in two geographically separated populations, which cannot be consistently distinguished morphologically: one mainly in scattered lowland prairie locations in the Puget Sound and Willamette Valley areas (the type collection came from this popula tion; no new collections have been taken from this region in over 65 years; it is likely extirpated) and another at high elevations in California, primarily in the Lake Tahoe region and southward in the Sierra Nevada.

Selected References

None.

Lower Taxa

None.

"fine" is not a number."elongating" is not a number.

... more about "Agoseris ×elata"
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
rounded;acute +
scarious +
ovate +  and lanceolate +
corymbiform +  and paniculiform +
indeterminate +  and determinate +
Gary I. Baird +
(Nuttall) Greene +
decurrent +
Stylopappus elatus +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
compound +  and simple +
obovate;lanceolate;oblanceolate +
15 cm150 mm <br />0.15 m <br /> (25 cm250 mm <br />0.25 m <br />) +
0.6 cm6 mm <br />0.006 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
tuberculate +, rugose +, muricate +  and smooth +
fusiform +
0.8 cm8 mm <br />0.008 m <br /> (1 cm10 mm <br />0.01 m <br />) +
filiform +
2 (?) +  and 6 (?) +
acute +, linear-lanceolate +  and cuneate-oblanceolate +
Willamette agoseris +
pistillate +  and staminate +
yellow +  and orange +
0.5 cm5 mm <br />0.005 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
1.1 cm11 mm <br />0.011 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
papillate +
tapered +, beaked +, flattened +, obcompressed +, compressed +, prismatic +, fusiform +, ellipsoid +, columnar +  and clavate +
Oreg. +, Wash. +, and montane meadows or open pine forests +, 1400–2800 m +  and Calif. +
10–100 m +
stipitate-glandular +, pubescent +  and villous +
winged +  and beaked +
dispersed +
Lowland prairies +
indeterminate +
each +  and sessile +
pistillate +  and staminate +
obconic;campanulate +
2 cm20 mm <br />0.02 m <br /> (4 cm40 mm <br />0.04 m <br />) +
sessile +  and petiolate +
erect +  and ascending +
cauline +  and basal +
0.8 cm8 mm <br />0.008 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
0.6 cm6 mm <br />0.006 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
antrorse;spreading +
lanceolate +  and triangular +
usually toothed +  and lobed or pinnatifid +
2-carpellate +
pistillate +  and staminate +
1 cm10 mm <br />0.01 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
0.6 cm6 mm <br />0.006 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
stipitate-glandular +, villous +, pubescent +  and glabrate +
Flowering Jun–Sep. +
connate +  and distinct +
subequal +  and unequal +
bearing subulate enations +, hairy +  and bristly +
flat;convex +
straight +
ridged +
exalbuminous +
prostrate +  and ascending +
appendaged +  and truncate +
papillate +
Agoseris grandiflora var. laciniata +, Agoseris laciniata +, Agoseris tenuifolia +, Stylopappus laciniatus +, Stylopappus laciniatus var. longifolius +, Troximon grandiflorum var. laciniatum +, Troximon grandiflorum var. tenuifolium +  and Troximon nuttallii +
Agoseris ×elata +
Agoseris +
species +
0.8 cm8 mm <br />0.008 m <br /> (1 cm10 mm <br />0.01 m <br />) +
perennial +, biennial +  and annual +