The Search for Coeloglossum

For several years while botanizing in Indiana, I had hoped to run across Frog Orchid (Coeloglossum viride). Vegetatively, this species can be confused with Palegreen Orchid (Platanthera flava var. herbiola) or even Broadleaf Helleborine (Epipactis helleborine). There have been a couple of times in the past when I thought I might have finally found this elusive, intriguing orchid, but it was not in flower so I could never be sure. Who knew that my search would be satisfied by freak chance in Colorado? In July 2009, at Holy Cross Wilderness Area when our vehicle was broken down, I was botanizing the area while waiting for Eric to return when I happened upon my long-time target.


Called Frog Orchid because the Gene Simmons tongue-like lip apparently resembles a frog hopping into cover (you'll need a little imagination to see this), Long-bracted Green Orchid, as it is also known, grows in the forests, meadows, and bogs in the montane and subalpine life zones in Colorado (Beidleman et al. 2000; Weber 1976). It is found worldwide with a circumpolar distribution (Sheviak & Catling 2002). In North America, Frog Orchid is known from most of Canada, Alaska, and the northern half of the continental United States east of the Rocky Mountains; it is also known less commonly from a few western states (NatureServe 2010). Its habitat includes moist to wet forests, thickets, bogs, prairies, and tundra (Sheviak & Catling 2002).


The photograph above shows a Frog Orchid plant in bloom. As you can see, the plant can be easily overlooked, as the green flowers blend in well with the surroundings.


Coeloglossum means "hollow tongue;" the genus was named for the hollow pouch-like nectary below the base of the flower lip (Homoya 1993). Some authors have now moved this only member of the genus Coeloglossum to the genus Dactylorhiza (in which case it is called Dactylorhiza viridis). Dactylorhiza literally means "finger root;" the roots of this species consist of several palmate tubers (Case 1987) that as a result look something like fingers. The long bracts subtending greenish flowers (seen above) are the source of the common name Long-bracted Green Orchid.


Frog Orchid is rare in these parts and can be difficult to see in shady forests. Be sure to watch for it in mature woods in late spring and summer.

Beidleman, L.H., R.G. Beidleman, & B.E. Willard. (2000). Plants of Rocky Mountain National Park. Estes Park, Colorado: Rocky Mountain Nature Association; Helena, Montana: Falcoln Publishing, Inc.

Case, F.W. Jr. (1987). Orchids of the Western Great Lakes Region. Bloomfield Hills, Michigan: Cranbrook Institute of Science.

Homoya, M.A. (1993). Orchids of Indiana. Bloomington & Indianapolis, Indiana: Indaian Academy of Science.

NatureServe. (2010). NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available http://www.natureserve.org/explorer. (Accessed: January 21, 2010 ).

Sheviak, C.J. & P.M. Catling. (2002). Coeloglossum. In: Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico. 15+ vols. New York and Oxford. Vol. 26.

Weber, W.A. (1976). Rocky Mountain Flora. Niwot, Colorado: University Press of Colorado.