Helenium microcephalum
littlehead tarweed, smallhead sneezeweed
1(2–10), branched distally, moderately to strongly winged, glabrous or sparsely hairy.
glabrous or sparsely to moderately hairy (basal withered by flowering);
proximal and mid blades narrowly elliptic to narrowly oblong-elliptic, usually serrate to undulate-serrate, sometimes deeply toothed or laciniate;
distal blades narrowly elliptic to narrowly oblong-elliptic, serrate to undulate-serrate.
1.8–8 cm, moderately hairy.
globoid to usually ovoid, 4–12 × 4–12 mm.
7–13, pistillate, fertile;
corollas usually yellow throughout, sometimes reddish proximally and yellow distally, 2.6–9.1 × 1.5–6.7 mm.
120–400+;
corollas yellow to yellow-green proximally, brown to reddish brown distally, 1.2–2.4 mm, lobes (4–)5.
(connate proximally) moderately hairy.
20–300+ per plant, in paniculiform arrays.
0.7–1.4 mm, moderately hairy;
pappi of usually 6 entire, non-aristate scales (0.2–)0.3–0.7 mm.
Helenium microcephalum
Varieties 2 (2 in the flora).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Peduncles 1–3.5 cm, projecting terminal heads barely beyond foliage; involucres 4–8 × 4–8 mm | var. microcephalum |
1. Peduncles 1.5–8 cm, usually projecting terminal heads well beyond foliage; involucres 8–12 × 8–12 mm | var. oöclinium |
WildflowerSearch
iNaturalist
USDA Plants Database
