General: Common Sunflower (Helianthus annuus) is an upright annual forb to about 10 feet with large, coarse leaves and large, yellow flowers with dark centers. The face of the central disk is more or less flat.

Common Sunflower is an uncommon component of disturbed desert vegetation communities. Around Las Vegas, look for this species in town and in disturbed roadsides and open fields such as at Corn Creek on the Desert National Wildlife Range.

This is an invasive weed in Nevada, and it is listed as a Noxious Weed in Iowa.

Family: Sunflower (Asteraceae).

Other Names: annual sunflower, wild sunflower

Plant Form: Upright, leafy annual.

Height: To about 10-12 feet.

Stems: Upright, branched, prickly.

Leaves: Leaves heart-shaped with coarse teeth, covered with stiff hairs that can be prickly, three veined, and long petioled. Lower leaves usually opposite, upper leaves alternate.

Flowers: Blooms during summer and fall. Flowers solitary on long peduncles. Ray flowers yellow, disk flowers brown. Ray flower petals about 1-inch long. Face of central disk usually flat.

Seeds: Sunflower seed.

Habitat: Disturbed sites, roadsides, old fields; often infests fertile soils.

Elevation: To about 6,000 feet.

Distribution: Throughout the US.

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