Senecio megacephalus

Nuttall

Trans. Amer. Philos. Soc., n. s. 7: 410. 1841.

Endemic
Treatment appears in FNA Volume 20. Treatment on page 553. Mentioned on page 547.

Perennials, (15–) 30–50 cm (rhizomes woody, suberect or creeping). Herbage loosely arachno-tomentose, unevenly glabrescent. Stems single or clustered. Leaves progressively reduced distally; weakly petiolate; blades lanceolate to narrowly oblanceolate, 10–18+ × 1–2 (–3+) cm, bases tapered, margins entire or wavy (often with dark, cartilaginous denticles; mid leaves similar, smaller, sessile; distal leaves bractlike). Heads usually 1 (sometimes subtended by 1–2 smaller heads). Calyculi of 5–8+ linear to filiform bractlets (lengths 1/2–7/8+ phyllaries). Phyllaries ± 21, 9–12 (–14) mm, tips not notably blackened (short-hairy). Ray-florets ± 13; corolla laminae (5–) 15–20 mm. Cypselae glabrous. 2n = 40.


Phenology: Flowering summer.
Habitat: Rocky, moist or drying sites, especially on mountain slopes
Elevation: 1500–2500 m

Distribution

V20-1220-distribution-map.gif

Alta., B.C., Idaho, Mont., Wyo.

Discussion

Selected References

None.

Lower Taxa

None.
... more about "Senecio megacephalus"
not tailed +, rounded +  and obtuse +
papillate +
scarious +
usually ovate +  and lance-linear +
racemiform +, paniculiform +, corymbiform +  and cymiform +
indeterminate +  and determinate +
Theodore M. Barkley† +
Nuttall +
tapered +
2 cm20 mm <br />0.02 m <br /> (3 cm30 mm <br />0.03 m <br />) +
10 cm100 mm <br />0.1 m <br /> (18 cm180 mm <br />0.18 m <br />) +
lanceolate;narrowly oblanceolate +
1cm;2cm +
winged;nerved;ribbed +
linear;filiform +
barbellulate +  and smooth +
white +  and stramineous +
purplish +, reddish +, white +, ochroleucous +, yellow +  and white rarely reddish +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (2 cm20 mm <br />0.02 m <br />) +
angled +, 5-ribbed +, prismatic +  and cylindric +
fertile +  and bisexual +
fertile +  and bisexual +
Alta. +, B.C. +, Idaho +, Mont. +  and Wyo. +
1500–2500 m +
hairy +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Rocky, moist or drying sites, especially on mountain slopes +
discoid +  and radiate +
indeterminate +
heterogamous +  and homogamous +
glabrescent +  and arachno-tomentose +
each +  and sessile +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
turbinate;campanulate +
cauline +  and basal +
reduced +
erect;recurved +
deltate +
dentate to pinnatifid +  and entire +
wavy +  and entire +
2-carpellate +
persistent +
Flowering summer. +
1.2 cm12 mm <br />0.012 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
mostly oblong +  and lanceolate or linear +
0.9 cm9 mm <br />0.009 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
Trans. Amer. Philos. Soc., n. s. +
bearing subulate enations +, hairy +  and bristly +
flat;convex +
exalbuminous +
appendaged +  and truncate +
papillate +
Compositae +
Senecio megacephalus +
species +
campanulate +
blackened +
denticulate +  and serrate or toothed +
15 cm150 mm <br />0.15 m <br /> (30 cm300 mm <br />0.3 m <br />) +
30 cm300 mm <br />0.3 m <br /> (50 cm500 mm <br />0.5 m <br />) +
shrub +  and subshrub +