About Helenium thurberi A.Gray
Helenium thurberi A.Gray, commonly called Thurber's sneezeweed, is a North American species of plant in the sunflower family. This species is native to Mexico, where it grows in Baja California Sur, Sinaloa, Nayarit, and Chihuahua, and to the southwestern United States, where it occurs in Arizona. It is an annual herb that can grow up to 100 cm (39.5 in) tall. Small wings run down along the sides of its stems, and its leaves are lance-shaped. A single plant can produce up to 120 flower heads arranged in a branching cluster. Each flower head has an egg-shaped or conical disc that holds 500 or more very small disc flowers. Each individual disc flower is 1.0–1.3 mm (0.039–0.051 in) across, yellow toward its base, and brown or reddish-brown toward its tip. This species has no ray flowers.
