Page authors: Don Knoke, David Giblin
Helianthus annuus
common sunflower
WTU specimens
Other herbaria

Distribution: Occurring chiefly east of the Cascades in Washington, but also on west side where escaped from cultivation.

Habitat: Open, dry to moderately moist soil; foothills, valleys and waste land.

Flowers: June-September

Origin: Native and introduced populations in Washington

Conservation Status: Not of concern

Description:
General:

Coarse annual, 4-20 dm. tall, the herbage rough-hairy.

Leaves:

Leaves chiefly alternate, long-petiolate, mostly toothed, ovate or broader, the lower often cordate.

Flowers:

Heads large, reddish-brown disk over 2 cm. wide; involucral bracts ovate, sub-equal, green, tapered to a point, covered with short, stiff hairs, with longer hairs on the margins; ray flowers large, yellow and neutral; receptacle chaffy throughout; pappus of 2 readily deciduous awns.

Fruits:

Achenes clasped by the inner involucral bracts.

Accepted Name:
Helianthus annuus L.
Publication: Sp. Pl. 2: 904. 1753.

Synonyms & Misapplications:
Helianthus annuus L. ssp. lenticularis (Douglas ex Lindl.) Cockerell
Additional Resources:

PNW Herbaria: Specimen records of Helianthus annuus in the Consortium of Pacific Northwest Herbaria database.

WA Flora Checklist: Helianthus annuus checklist entry.

E-Flora BC: Helianthus annuus atlas page.

CalPhotos: Helianthus annuus photos.

USDA Plants: Helianthus annuus information.

40 photographs:
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