Common sunflower

Common sunflower is a widely branching, stout annual, 1 1/2-8 ft. tall, with coarsely hairy leaves and stems. The terminal flowers heads are large and showy, up to 5 in. across. A tall, coarse leafy plant with a hairy stem commonly branched in the upper half and bearing several or many flower heads, the central maroon disk surrounded by many bright yellow rays. Yellow ray flowers surround brown disk flowers. The state flower of Kansas. Contrary to common myth, the heads of sunflowers do not follow the sun each day. However, developing flower buds and leaves do exhibit some phototropism. The plant has been cultivated in Central North America since pre-Columbian times; yellow dye obtained from the flowers, and a black or dull blue dye from the seeds, were once important in Native American basketry and weaving. Native Americans also ground the seeds for flour and used its oil for cooking and dressing hair. It was believed, in the 19th century, that plants growing near a home would protect from malaria. Seeds from cultivated strains are now used for cooking oil and livestock feed in the United States and Eurasia. Many variants have been developed, some with one huge head topping a stalk 9-16 ft (3-5 m) tall, others with maroon rays. Prairie Sunflower (H. petiolaris), found throughout the Great Plains and similar to the wild forms of Common Sunflower, has scales on the disk in the center of the head tipped by white hairs, easily visible when the central flowers are spread apart. Developed in a single large head variety by Russians.