Senecio flaccidus

Lessing

Linnaea 5: 161. 1830.

Illustrated
Treatment appears in FNA Volume 20. Treatment on page 558. Mentioned on page 548, 559.

Subshrubs or shrubs, (30–) 40–120+ cm (taproots forming woody crowns). Herbage glabrous or ± lanate-tomentose. Stems usually multiple (little branched, arching-erect). Leaves ± evenly distributed; sessile or obscurely petiolate; blades narrowly linear to filiform (or pinnatifid, the segments linear to filiform), 3–10 (–12) cm, bases ± linear, ultimate margins entire or remotely toothed (fascicles of smaller leaves sometimes borne in axils of larger leaves). Heads (1–) 3–10 (–20+) in corymbiform or subcorymbiform clusters, often gathered in larger, showy arrays (involucres campanulate or cylindric). Calyculi usually of 3–5+ bractlets (lengths often to 1/2+ phyllaries), sometimes 0. Phyllaries ± 13 or ± 21+, 5–10 (–12) mm, tips green or minutely black. Ray-florets usually ± 8 or ± 13, sometimes ± 21; corolla laminae 10–15 (–20) mm (mostly yellow, sometimes ochroleucous). Cypselae hairy. 2n = 40.

Distribution

V20-1238-distribution-map.gif

Ariz., Calif., Colo., Kans., N.Mex., Nev., Okla., Tex., Utah, Mexico

Discussion

Varieties 3 (3 in the flora).

The varieties of Senecio flaccidus are distinguished by morphologic tendencies and geography. The species occurs southward to central Mexico; a sound understanding of the infraspecific taxonomy must await revisionary studies that include the Mexican plants.

Selected References

None.

Key

1 Herbage usually tomentose (hairs whitish), sometimes unevenly glabrescent; bractlets of calyculi minute or 0; involucres cylindric or ± campanulate; phyllaries ± 13 or ± 21, 5–8+ mm Senecio flaccidus var. flaccidus
1 Herbage ± tomentose, glabrate, or glabrous; bractlets of calyculi well developed (lengths mostly 1/3 – 1/2 phyllaries); involucres ± campanulate; phyllaries ± 21, 7–12 mm > 2
2 Plants usually ± tomentose (usually with persistent, uneven grayish tomentum), sometimes unevenly glabrescent; California w of crests of Sierra Nevada and related ranges Senecio flaccidus var. douglasii
2 Plants glabrate or glabrous; California deserts e of crest of Sierra Nevada and eastward Senecio flaccidus var. monoensis
... more about "Senecio flaccidus"
not tailed +, rounded +  and obtuse +
papillate +
scarious +
usually ovate +  and lance-linear +
racemiform +, paniculiform +, corymbiform +  and cymiform +
indeterminate +  and determinate +
Theodore M. Barkley† +
Lessing +
decurrent +
10 cm100 mm <br />0.1 m <br /> (12 cm120 mm <br />0.12 m <br />) +
narrowly linear;filiform +
3 cm30 mm <br />0.03 m <br /> (10 cm100 mm <br />0.1 m <br />) +
winged;nerved;ribbed +
barbellulate +  and smooth +
white +  and stramineous +
purplish +, reddish +, white +, ochroleucous +, yellow +  and white rarely reddish +
1.5 cm15 mm <br />0.015 m <br /> (2 cm20 mm <br />0.02 m <br />) +
1 cm10 mm <br />0.01 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
angled +, 5-ribbed +, prismatic +  and cylindric +
fertile +  and bisexual +
fertile +  and bisexual +
Ariz. +, Calif. +, Colo. +, Kans. +, N.Mex. +, Nev. +, Okla. +, Tex. +, Utah +  and Mexico +
hairy +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
discoid +  and radiate +
indeterminate +
heterogamous +  and homogamous +
lanate-tomentose +  and glabrous +
each +  and sessile +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
turbinate;campanulate +
petiolate +  and sessile +
distributed +
cauline +  and basal +
erect;recurved +
deltate +
dentate to pinnatifid +  and entire +
2-carpellate +
persistent +
1 cm10 mm <br />0.01 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
mostly oblong +  and lanceolate or linear +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
bearing subulate enations +, hairy +  and bristly +
flat;convex +
exalbuminous +
Illustrated +
appendaged +  and truncate +
papillate +
Compositae +
Senecio flaccidus +
species +
campanulate +
black +  and green +
toothed +  and entire +
perennial +, biennial +  and annual +
shrub +  and subshrub +