Helianthus annuus
Helianthus glaucophyllus
common sunflower, hairy leaf sunflower, sunflower
whiteleaf sunflower
erect, usually hispid.
erect, glabrous (glaucous).
mostly cauline; mostly alternate;
petioles 2–20 cm;
blades lance-ovate to ovate, 10–40 × 5–40 cm, bases cuneate to subcordate or cordate, margins serrate, abaxial faces usually ± hispid, sometimes gland-dotted.
mostly cauline; opposite (proximal) or alternate;
petioles 1–3 cm;
blades (light to dark green, abaxially whitish, 3-nerved), lanceolate to lance-ovate, 9–18 × 2.5–7 cm, bases abruptly narrowed, margins serrate, faces glabrous (abaxial) or sparsely scabrous (adaxial), not gland-dotted (abaxial glaucous).
2–20 cm.
0.5–8 cm.
hemispheric or broader, 15–40(–200+) mm diam.
hemispheric, 8–9 mm diam.
(13–)17–30(–100+);
laminae 25–50 mm.
5–8;
laminae 12–14 mm (abaxial faces not gland-dotted).
150+(–1000+);
corollas 5–8 mm (throats ± bulbous at bases), lobes usually reddish, sometimes yellow;
anthers brownish to black, appendages yellow or dark (style branches yellow).
20–35;
corollas 5–6 mm, lobes yellow;
anthers dark, appendages dark.
20–30(–100+), ovate to lance-ovate, 13–25 × (3–)5–8 mm, (margins usually ciliate) apices abruptly narrowed, long-acuminate, abaxial faces usually hirsute to hispid, rarely glabrate or glabrous, usually gland-dotted.
12–15, lanceolate to ovate, 8–9 × 1.8–3 mm, (margins ciliate) apices acuminate.
1–9.
3–15+.
(3–)4–5(–15) mm, glabrate;
pappi of 2 lanceolate scales 2–3.5 mm plus 0–4 obtuse scales 0.5–1 mm.
3.5–3.8 mm, glabrous;
pappi of 2 aristate scales 3.2–3.5 mm.
9–11 mm, 3-toothed (middle teeth long-acuminate, glabrous or hispid).
6.2–7.5 mm, 3-toothed (apices hairy).
= 34.
= 34.
Helianthus annuus
Helianthus glaucophyllus
Helianthus annuus is widely distributed, including weedy, cultivated, and escaped plants. It is the only native North American species to become a major agronomic crop. Despite its considerable variability, attempts have failed to produce a widely adopted infraspecific system of classification. Forms with red-colored ray laminae, known from cultivation and occasionally seen escaped, trace their ancestry to a single original mutant plant. It hybridizes with many of the other annual species.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Helianthus glaucophyllus is found in the southern Blue Ridge Province. It is distinguished from H. microcephalus, with which it shares relatively small heads, by glabrous or sparsely scabrous, glaucous leaves. Its closest relative may be H. decapetalus, which has larger heads and, usually, longer phyllaries.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
- Local floras:
BC, 
CA, 
OR, 
WA - Local Web sites: CalFlora, CalPhotos,
Flora NW, 
Go Botany, 
IL Wildflowers, 
KS Wildflowers, 
LA Plants, 
MD Biodiversity, 
MI Flora, 
MN Wildflowers, 
MO Plants, 
PNW Herbaria, 
SW CO Wildflowers, Turner Photog. 
WildflowerSearch
iNaturalist (observations)
USDA Plants Database- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
