The Carlisle Mosquito Online

Friday, September 30, 2005

Features


Nodding Ladies' Tresses Orchid

(Photo by Tom Brownrigg)

Kay Fairweather and I discovered a Nodding Ladies' Tresses Orchid Spiranthes cernua blooming in a sunny damp field where sundews were growing (Carlisle Mosquito, September 16, 2005). It had just started to bloom on September 5. I later found several plants blooming at Towle Field on September 13, and at Great Brook Farm State Park on September 21. This orchid reportedly blooms into October, definitely a late-bloomer!

If you walk the woods of Carlisle, you have probably seen the large, showy Pink Lady's Slipper Orchid that blooms in May (Carlisle Mosquito, May 30, 2003). However, many native orchids are much less conspicuous, an example being Rattlesnake Plantain, a relatively common woodland orchid with tiny flowers and leaves resembling snake skin (Carlisle Mosquito, December 5, 2003).

S. cernua is small with many white flowers borne densely on a single flower spike, typically 6-12 inches tall. It would probably be completely overlooked if it were not blooming, since the leaves resemble blades of grass, and appear to die back as the flowers develop. The largest flowers, at the bottom of the spike, are about 10 mm (0.4 in.) long, measured from the sepals. The lower front part of the flower, called the lip, is divided into two rounded lobes. The flowers are bent back at a right angle to the spike in a spiral arrangement, hence the generic name Spiranthes. The web site of the Connecticut Botanical Society (1) has excellent photos of the flowers, and is a very useful resource for other New England wildflowers.

Nodding Ladies' Tresses is the second small and rather inconspicuous orchid found at Towle field. The other is Ragged Fringed Orchid, Platanthera lacera, featured in the August 13, 2004 Carlisle Mosquito. Could there be others? There are over 30 species in this genus (2), although S. cernua is the most common of seven species found in Connecticut (1). These orchids like wet, sunny places, and you might find cranberries growing in the same location.

References: 1. Connecticut Botanical Society: www.ct-botanical-society.org/galleries/spiranthescern.html; 2. Monica Gupta: www.discoverlife.org/nh/tx/Plantae/Monocotyledoneae/Orchidaceae/Spiranthes/cernua/.


2005 The Carlisle Mosquito