Helianthus annuus, the common sunflower, is a large annual forb of the genus Helianthus grown as a crop for its edible oil and edible fruits. This sunflower species is also used as wild bird food, as livestock forage (as a meal or a silage plant), in some industrial applications, and as an ornamental in domestic gardens. Sunflower is one of the best plants to compete against weeds, thanks to the highly developed foliage; at the same time, through the very powerful radicular system it exhausts the soil, generally avoiding the sowing of the wheat after this culture.
