Common sunflower

The common sunflower (Helianthus annuus) is a species of large annual forb of the daisy family Asteraceae. The common sunflower is harvested for its edible oily seeds, which are often eaten as a snack food. They are also used in the production of cooking oil, as food for livestock, as bird food, and as a plantings in domestic gardens for aesthetics. Wild plants are known for their multiple flower heads, whereas the domestic sunflower often possesses a single large flower head atop an unbranched stem.

The plant has an erect rough-hairy stem, reaching typical heights of 3 metres (10 feet). The tallest sunflower on record achieved 9.17 m (30 ft 1 in). Sunflower leaves are broad, coarsely toothed, rough and mostly alternate; those near the bottom are largest and commonly heart-shaped.

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