USGS - science for a changing world

Northern Prairie Wildlife Research Center

  Home About NPWRC Our Science Staff Employment Contacts Common Questions About the Site

Aquatic and Wetland Vascular Plants of the Northern Great Plains

49. Asteraceae, the Aster Family

12. Helianthus L. -- Sunflower

2. Helianthus nuttallii T. & G. -- Nuttall's sunflower

Similar to the preceding and grading into it in the e part of our region, differing mainly as follows: Smaller in stature, 0.4-2 m tall; stem glabrous or sometimes hispid in the middle and lower portions, strigose in the inflorescence. Leaf blades narrowly lanceolate to lanceolate or ovate-lanceolate to elliptic, 4-15(20) cm long, 0.8-4.5 cm wide, entire to shallowly toothed, cuneate to rounded at the base; petioles 0.5-2(4) cm long. Jul--Sep. Wet meadows, marshes, shores, stream banks, ditches and other wet places; nw, c and e ND, across SD and e WY and s to c NE; (MN to Sask. and se B.C., s to NE, NM, AZ and CA). H. rydbergii Britt.

Two phases of H. nuttallii are encountered in our region. H. nuttallii subsp. rydbergii (Britt.) Long is most common, with mostly opposite, ovate-lanceolate to lanceolate or elliptic leaves, acute to obtuse at the tip. The other phase is subsp. nuttallii, with mostly alternate, linear-lanceolate to narrowly lanceolate leaves, acute to acuminate at the tip.

In the e part of our region where H. nuttallii and H. grosseserratus overlap in range, intermediate populations are found which cannot be assigned to either species with confidence.

gifsGIF- Distribution Map

Map key

Previous Section -- Helianthus grosseserratus Martens -- Sawtooth sunflower
Return to Family -- Asteraceae - The Aster Family
Next Section -- Petasites frigidus (L.) Fries

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo logo U.S. Department of the Interior | U.S. Geological Survey
Page Contact Information: Webmaster
Page Last Modified: Saturday, 02-Feb-2013 06:43:32 EST
Sioux Falls, SD [sdww55]