Northern Prairie Wildlife Research Center
One of our most abundant sunflowers, plains sunflower has been collected in nearly every county in North Dakota. The species probably originally ranged from Wisconsin to Alberta south to Georgia and Arizona, but since its discovery has spread from Maine to British Columbia and California, at elevations up to 8,000 ft.
Unlike most of our wild sunflowers, plains sunflower is a taprooted annual. Plants are up to four feet tall. Leaves are nearly all alternate, rather than opposite each other on the stem. These leaves are deltoid to oval and up to six inches long. All have a stalk called a petiole. Only a few flower heads are formed. These are usually about an inch and a half wide including the 15-30 yellow rays. The tiny center (disc) flowers are usually reddish-purple. Fruits are typical sunflower achenes about a quarter inch long.
Look for plains sunflower from June through September in open sandy prairie and along roadsides. More plants will be found where grazing is light or moderate. Many of the 60 or so species of sunflower are used for foods, medicines, and industrial products, but plains sunflower has no known economic value other than forage.
Plains sunflower is, of course, a member of the sunflower family (Asteraceae). Aster means "star" in Greek, in reference to the radiate arrangement of flowers in the heads. The sunflower family is by far the largest in North Dakota and in most temperate areas of the Northern Hemisphere. The generic name Helianthus stems from the Greek helios, "the sun," and anthos, "a flower." The specific epithet petiolaris means "having a petiole" in botanical Latin. Plains sunflower was first described for science in 1821 by the famous naturalist, botanist, and ornithologist, Thomas Nuttall (1786-1859). Nuttall visited the Mandan villages in what is now North Dakota in 1810-1811.