Sunday, June 08, 2008

Achlorophyllous Epipactis

Some neighbours drew my attention to this strange plant growing at the entrance to a plot about 50 yards up the road from our house. It is an achlorophyllous helleborine orchid, probably the broad-leaved helleborine (Epipactis helleborine), that has developed without chlorophyll. This is something that happens from time to time in this genus and there is a good picture of an achlorophyllous violet helleborine (E. purpurata) on page 53 of David Lang's Wild Orchids of Sussex (Pomegranate Press, 2001). Other wild orchids, such as the bird's-nest orchid (Neottia nidus-avis) are always chlorophyll-free so it looks as though some Epipactis may be evolving in this direction. It is thought that, in the absence of chlorophyll, the plants depend entirely on a myorrhizal fungus for their nutrition. I will post some more pictures if the plant survives and flowers.