Senecio spartioides
Senecio arizonicus
broom groundsel, broom senecio, broom-like ragwort, grass-leaf ragwort, many-head groundsel
Arizona ragwort
usually glabrous, sometimes sparsely, unevenly hairy.
lanate-arachnose or tomentose, unevenly glabrescent.
usually multiple (branching and arching upward).
1(–2).
evenly distributed (proximal often smaller);
sessile or obscurely petiolate;
blades narrowly linear to filiform (or parted into linear-filiform lobes), 5–10 cm × 1–6 mm, bases ± linear, ultimate margins entire.
(often purplish abaxially) reduced distally; petiolate;
blades ovate to subelliptic, (5–)6–10(–15) × (2.5–)3–5(–9) cm, bases tapered or contracted, margins subentire to denticulate (denticles callous; mid and distal leaves bractlike).
± 5 (± 13);
corolla laminae 8–12 mm.
± 13;
corolla laminae 5–10 mm.
usually ± 8, sometimes ± 13, (5–)6–9(–10) mm, tips green or minutely black.
(± 13) ± 21, 5–7 mm, tips green.
0 or of 1–3+ (minute, inconspicuous) bractlets.
of 2–5+ bractlets (largest to 3 mm).
10–20(–60) in compound corymbiform arrays (involucres cylindric or narrowly campanulate, 3–6 mm diam.).
(2–)5–12(–20) in corymbiform arrays.
usually hirtellous, sometimes glabrous.
hairy (especially on angles).
= 40.
= 40.
Senecio spartioides
Senecio arizonicus
Plants with the leaves parted into lobes that are seldom more than 1 mm wide have been recognized as Senecio spartioides var. multicapitatus (or as S. multicapitatus); expression of the character is inconsistent throughout the range and recognition of the two entities is all but impossible to maintain.
Senecio spartioides apparently hybridizes with S. eremophilus in Garfield County, Utah, and perhaps elsewhere (cf., Holmgren, Reveal, and LaFrance 3463, BRY, KSC, NY). The name Senecio toiyabensis rests upon materials that suggest introgression with S. fremontii. Some specimens usually referred to 41. S. pattersonensis suggest introgression with S. spartioides.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Senecio arizonicus is reputedly in southern New Mexico (W. C. Martin and C. R. Hutchins 1980); that seems unlikely and should be checked.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
CA
SW CO Wildflowers
WildflowerSearch
iNaturalist
USDA Plants Database
