Senecio flaccidus
Senecio triangularis
Douglas' groundsel, Mono groundsel, shrubby butterweed, shrubby ragwort, threadleaf groundsel, threadleaf ragwort
arrow-leaf groundsel, arrow-leaf ragwort, arrowleaf butterweed, groundsel
glabrous or ± lanate-tomentose.
glabrous or sparsely floccose-tomentose when young.
usually multiple (little branched, arching-erect).
single or loosely clustered.
± 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).
evenly distributed; petiolate;
blades narrowly triangular, (3–)4–10+ × 2–6 cm, bases usually ± truncate, sometimes tapered, margins usually dentate, rarely subentire (distal leaves subsessile, smaller).
usually ± 8 or ± 13, sometimes ± 21;
corolla laminae 10–15(–20) mm (mostly yellow, sometimes ochroleucous).
± 8;
corolla laminae 9–15 mm.
± 13 or ± 21+, 5–10(–12) mm, tips green or minutely black.
(± 8) ± 13 (± 21), 6–10 mm, tips usually green, rarely black.
usually of 3–5+ bractlets (lengths often to 1/2+ phyllaries), sometimes 0.
of 2–6 bractlets (rarely more than 2 mm).
(1–)3–10(–20+) in corymbiform or subcorymbiform clusters, often gathered in larger, showy arrays (involucres campanulate or cylindric).
10–30(–60) in corymbiform to subracemiform arrays.
hairy.
glabrous.
= 40.
= 40, 80.
Senecio flaccidus
Senecio triangularis
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.)
Plants of Senecio triangularis with narrow, subentire leaves that taper to the petioles are occasionally encountered in acid bogs in Oregon and Washington and less frequently elsewhere. They are regarded as edaphic variants; they have been recognized as var. angustifolius.
(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
BC
OR
WA
Flora NW
PNW Herbaria
SW CO Wildflowers
