Common Sunflower

Helianthus annuus ssp. lenticularis

Family: Asteraceae (A Utah Flora – Compositae) – Sunflower Family

Annual herbs; stems 11.8” to 13.1' (3 to 40 dm) tall

Leaves: opposite below; alternate above; simple; 1.2” to 1.3' (3 to 40 cm) long, 0.8” to 1.3' (2 to 40 cm) wide; has hairs

Flowers: yellow ray flowers; disks 0.8” to 2” (2 to 5 cm) wide or more; disk corolla lobes purplish red or rarely yellow; perfect; flower head appears to be a single flower, but is composed of several flowers (a composite)

Pollinators: bees and flies

Fruits: achene – 1 seeded with hard shell

Blooms in Arches National Park: April, May, June, July, August, September, October, early November

Habitat in Arches National Park: riparian, desert shrub, grassland and pinyon-juniper communities

Other: The genus name, “Helianthus”, is derived from the Greek words “helios” , which means "sun" and “anthos” which means "flower" and refers to the flower's habit of turning with the sun. The species name, “annuus”, means “annual”; the subspecies name, “lenticularis”, means “lens-shaped”.

This family is the most advanced and complex of the dicots. The family is rich in oils and resins and is found in every part of the world, but is infrequent in the tropical rainforest. Aquatic or semi-aquatic species are also uncommon.