Common Sunflower: Helianthus annuus (Synonyms: Helianthus annuus ssp. annuus, Helianthus annuus ssp. lenticularis) - Annual. Herbage harshly pubescent. Broad triangular leaf blades with slightly toothed margins. Leaf is a dull dark green. One single, stout stem bears several flower heads of numerous yellow ray flowers and a reddish brown central disk. 1-10 feet tall.
Texas Blueweed: Helianthus ciliaris -
Cusick's Sunflower, Turniproot Sunflower: Helianthus cusickii - Perennial. Herbage harshly pubescent. Prostrate to erect plant, with many stems. Flower heads "sunflower-like" with both yellow ray and discoid flowers. Leaves linear or lanceolate. To three feet tall.
Sawtooth Sunflower: Helianthus grosseserratus -
Nuttall's Sunflower, Cordilleran Sunflower: Helianthus nuttallii ssp. nuttallii (Synonym: Helianthus nuttallii var. nuttallii) - Perennial. Herbage glabrous and glaucous. Leaves opposite, narrowly lanceolate to lance-oblong with acuminate tips. Flower heads "sunflower-like" with yellow rays and disk flowers.
Prairie Sunflower: Helianthus petiolaris ssp. petiolaris (Synonyms: Helianthus petiolaris, Helianthus petiolaris var. petiolaris) - Collected in Gilliam and Sherman Counties in north-central Oregon, and near Silver Lake, OR.
Jerusalum Artichoke: Helianthus tuberosus - Escaped garden plant. Forms edible tubers. Garden escapees occasionally become established in the wild around old homesteads.