Common: Common Sunflower
Native to western North America, now distributed throughout most of US
Sunflower is a familiar flower found growing both in the garden and along the roadside. There are several species grown in gardens, including cultivars having mammoth flower heads. The approximately 75 species of sunflowers are all native to the New World, and some are common annual or perennial wildflowers; however, they are cultivated in other parts of the world, especially Russia and Argentina. Sunflowers are cultivated as a crop, especially in the north central US, for their oil-bearing seeds which comprise the world’s second-most important oil-bearing crop. The common sunflower, an annual, may reach 15 feet in height and bear both a terminal flower head (generally the largest, usually exceeding 4 inches in diameter, but may be a foot in some cultivars) and additional flower heads on branches. The simple triangular leaves are arranged alternately on the stem with smaller ones near the top and on the branches while those lower on the stem may reach a foot in length. The flower heads, particularly the terminal (top) ones, are famous for turning to face the sun during the course of a day. One may be allergic to the pollen and/or to the seeds, and some individuals develop rashes from contact with the foliage.