- Agriculture, Forestry & Soils
- Field crops, grasses, plant fibers, spices, tree crops, herbs
Beard, Benjamin H. Agronomy and Range Science, Agricultural Research Western Region, U.S. Department of Agriculture, Davis, California.
Orellana, Rodrigo G. Institute of Plant Protection, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, Maryland.
- Economic importance and distribution
- Related Primary Literature
- Additional Reading
An annual plant, Helianthus annuus, which is native to North America and characterized by broad, ovate leaves growing from a single, usually long stem, and large, composite flowers with yellow petals. Helianthus annuus (Fig. 1) is the most widely distributed of the approximately 70 native North American species of the genus Helianthus of the family Asteraceae (Compositae). In general, the sunflower is an extremely variable species, with two main divisions. The first involves wild weedy plants found along roadways and other recently disturbed areas; the second involves domesticated plants grown in fields and gardens. See also: Asterales
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