Senecio flaccidus
Senecio aronicoides
Douglas' groundsel, Mono groundsel, shrubby butterweed, shrubby ragwort, threadleaf groundsel, threadleaf ragwort
butterweed, rayless groundsel, rayless ragwort
glabrous or ± lanate-tomentose.
loosely and sparsely arachnose to finely tomentose, unevenly glabrescent.
usually multiple (little branched, arching-erect).
single.
± 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).
progressively reduced distally; petiolate;
blades ovate or oblanceolate to oblong, 7–20 × 2–3 cm, bases broadly to narrowly tapered, margins repand-denticulate or sublaciniate to subentire (mid and distal leaves sessile, smaller, weakly clasping).
usually ± 8 or ± 13, sometimes ± 21;
corolla laminae 10–15(–20) mm (mostly yellow, sometimes ochroleucous).
0 or 1–2;
corolla laminae 4–7 mm.
± 13 or ± 21+, 5–10(–12) mm, tips green or minutely black.
± 8 or ± 13, 4–8 mm, tips green or black.
usually of 3–5+ bractlets (lengths often to 1/2+ phyllaries), sometimes 0.
0 or of 1–3+ oblong to linear bractlets (seldom more than 1.5 mm).
(1–)3–10(–20+) in corymbiform or subcorymbiform clusters, often gathered in larger, showy arrays (involucres campanulate or cylindric).
(6–)15–30+ in corymbiform arrays.
hairy.
glabrous.
= 40.
= 40.
Senecio flaccidus
Senecio aronicoides
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.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
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 | 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 | var. douglasii |
2. Plants glabrate or glabrous; California deserts e of crest of Sierra Nevada and eastward | var. monoensis |
CA
KS Wildflowers
WildflowerSearch
iNaturalist
USDA Plants Database
OR
Flora NW
PNW Herbaria
