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Native Wildflowers of the North Dakota Grasslands

JPG -- species photo

Stemless Hymenoxys (Hymenoxys acaulis)


Restricted in distribution to the western one-third of North Dakota, stemless hymenoxys occurs throughout most of the western United States and southern Saskatchewan. The plant has also rarely been found in several locations east of the Mississippi River. In western mountain ranges plants have been collected at elevations up to 12,000 feet.

The plant has no stem. Instead, the structure supporting the flower head is a leafless organ called a scape. North Dakota specimens of stemless hymenoxys are up to 10 inches tall and perennial from a crown of tough old bases from previous years' growth. This crown is at the top of a woody taproot. Leaves are all basal, silvery green with short hairs, about 2 inches long and a quarter inch wide. Flower heads are solitary and about 3/4 inch wide, with pale yellow rays that bend downward at maturity. Fruits are fuzzy achenes about 1/8-inch long.

Look for stemless hymenoxys in dry soils of the high prairie and among rocky breaks in the badlands. Cattle seem to avoid the plant, and it seems slightly more abundant where grazing is moderate or heavy. One southern Hymenoxys is poisonous to livestock, especially sheep, but stemless hymenoxys likely is harmless.

Stemless hymenoxys is a member of the sunflower family (Asteraceae) of which there are about 15,000 species worldwide and about 200 species in North Dakota. The generic name was compounded from the Greek humen "membrane" and oxys "sour", likely in allusion to the translucent scales at the base of the flowers and the sour or bitter taste of several of the species. Acaulis means "without a stem" in botanical Latin. The plant was first described under another genus by Frederick Pursh (1774-1815), and later placed into the genus Hymenoxys by Kittie Lucille (Fenley) Parker (1910- ), a specialist in the Asteraceae of the southwest United States.


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