Helianthus hirsutus
Helianthus smithii
hairy sunflower
Smith's sunflower
erect, hirsute.
(usually purplish) erect, glabrous (glaucous).
cauline; mostly opposite;
petioles 0.4–2 cm;
blades (3-nerved from bases) lanceolate to ovate, 6.5–18 × 1–8 cm, bases truncate to broadly rounded or cuneate, margins subentire to serrate (flat), abaxial faces ± hirsute, gland-dotted (adaxial not gland-dotted).
cauline; opposite (proximal) or alternate;
petioles to 1.3 cm;
blades (light to dark green, 1-nerved) lance-linear to lanceolate, 7–18 × 1–1.8 cm, bases ± cuneate, margins serrulate, abaxial faces ± hispid, gland-dotted.
1–5 cm.
3–6 cm.
hemispheric, 10–25 mm diam.
hemispheric, 5–15 mm diam.
10–15;
laminae 15–20 mm.
6–9;
laminae 10–15 mm.
40+;
corollas 5.5–6.5 mm, lobes yellow;
anthers dark brown or black, appendages dark or yellowish.
25+;
corollas 5.5–6 mm, lobes yellow;
anthers dark, appendages dark.
18–25 (usually loose, spreading, not reflexed), lanceolate, 7–12 × 2.5–3.5 mm, (margins ciliate) apices acute to short-acuminate, abaxial faces not gland-dotted.
15–20, lanceolate, 6–9 × 2–2.7 mm, (margins ciliate) apices short-acuminate, abaxial faces glabrous or glabrate, not gland-dotted.
1–7.
1–5.
4–4.5 mm, glabrate or distally puberulent;
pappi of 2 aristate scales 2.5–3.2 mm.
2.8–3 mm, glabrate;
pappi of 2 aristate scales 1.5–2 mm.
7–10 mm, 3-toothed (apices yellowish, hairy).
5.5–6.5 mm, 3-toothed (gland-dotted).
= 68.
= 68.
Helianthus hirsutus
Helianthus smithii
Helianthus hirsutus is distinguished from H. strumosus by hairy stems and usually yellow (as opposed to dark) anther appendages, and from H. divaricatus by petioles and leaf blades 3-nerved distal to bases. Mexican plants of H. hirsutus are sometimes labeled with the synonymous H. leptocaulis (S. Watson) S. F. Blake, and plants from Mexico and the southwestern United States often have leaf bases cuneate rather than truncate.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Of conservation concern.
Helianthus smithii is known from relatively few sites. T. A. Storbeck (1984) concluded that it is a distinct species; he could not rule out the possibility that it might be a hybrid of H. microcephalus and H. strumosus. It may also be an extreme variant of H. strumosus that has relatively narrow leaves and small heads.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Go Botany
IL Wildflowers
KS Wildflowers
LA Plants
MD Biodiversity
MI Flora
MN Wildflowers
MO Plants
WildflowerSearch
iNaturalist
USDA Plants Database
