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Native Wildflowers of the North Dakota Grasslands

JPG -- species photo

Nodding Ladies-tresses (Spiranthes cernua)


In North Dakota, nodding ladies-tresses has been found at scattered locations east of the Missouri River. The plant is found throughout most of our eastern states.

Nodding ladies-tresses is a perennial that, in our area, usually grows about 8-10 inches tall. Roots are fleshy and tuberous. Long narrow leaves arise mostly from the base of the stem but do not overtop the flowers. The 3-inch long flowering spikes are very striking because 3 rows of drooping white flowers are twisted around a central axis. For this reason, the plant is sometimes called "screw-auger" or "pearl twist."

Look for nodding ladies-tresses on moist native grassland. The plant is never very abundant and has no known value for forage or medicine.

Nodding ladies-tresses belongs to the cosmopolitan orchid family (Orchidaceae), which is the largest in the world with 500 genera and about 20,000 species. Orchids depend on soil fungi for part of their food and some species are entirely devoid of chlorophyll. Some tropical species live underground for a considerable period of time before aboveground stems and leaves are produced. The generic name Spiranthes derives its name from the Greek speira, "a coil" and anthos, "flower," concerning the twisted spike. The specific epithet cernua means "nodding" as applied to the flowers. Nodding ladies-tresses was first described for science in 1753 by the great Swedish naturalist and father of modern botany, Carl von Linne (Linnaeus).


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Page Last Modified: Saturday, 02-Feb-2013 06:52:50 EST
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