Epipactis helleborine


Epipactis helleborine, the broad-leaved helleborine, is a terrestrial species of orchid with a broad distribution. Its nodding flowers vary from greenish pink to purple. It prefers shaded woodland environments.

Description

Epipactis helleborine grows to a maximum height of and has broad dull green leaves which are strongly ribbed and flat. The flowers are arranged in long drooping racemes with dull green sepals and shorter upper petals. The lower labellum is pale red and is much shorter than the upper petals.
Achlorophyllous, white Epipactis helleborine plants have been found. Achlorophyllous forms tend to be shorter, as small as 17cm.
Flowering occurs June-September.

Distribution

This species is widespread across much of Europe and Asia, from Portugal to China, as well as northern Africa.
In North America, it is an introduced species and widely naturalized mostly in the Northeastern United States, eastern Canada and the Great Lakes Region, but also in scattered locations in other parts of the continent. In the US it is sometimes referred to as the "weed orchid" or "weedy orchid" and continues to spread throughout the country to new areas including Michigan, Wisconsin, and the San Francisco Bay Area.

Habitat

Found in woods and hedge-banks and often not far from paths near human activity. It is one of the most likely European orchids to be found within a city, with many sites for example in Glasgow, London and Moscow. Sometimes spotted beside car parks.

Ecology

This species of orchid is pollinated by several species of Hymenoptera, particularly the common wasp, but also other species in the genera Vespula and Dolichovespula. Flowers release a sweet nectar to attract the wasps, which has an intoxicating effect on them. Eight varieties of Epipactis helleborine in central Europe had their nectar studied and they were found to contain naturally occurring oxycodone in minute amounts.
Epipactis helleborine requires a mycorrhizal symbiosis to germinate successfully and remains partially dependent upon the fungus when plants mature, however it is not particularly selective among fungal species. Fungi associated with the live roots include Tuber, Helotiales, Peziza, Leptodontidium, Hydnotrya and Wilcoxina.
It has been suggested that the presence of this orchid species in a woodland is an indicator that edible truffles can be found there, but this is not always the case.

Subspecies

A rather long list of names have been proposed for subspecies, varieties and forms of Epipactis helleborine, far too many to list here. This is not unusual for such a widespread species. At present only the following are accorded international acceptance:
  1. Epipactis helleborine subsp. bithynica Kreutz - Turkey
  2. Epipactis helleborine subsp. degenii Kreutz - Greece
  3. Epipactis helleborine subsp. densifolia Kreutz - Turkey
  4. Epipactis helleborine subsp. helleborine - widespread
  5. Epipactis helleborine subsp. latina W.Rossi & E.Klein - Italy, former Yugoslavia
  6. Epipactis helleborine subsp. leutei Kreutz - Austria, Czech Republic
  7. Epipactis helleborine subsp. levantina Kreutz, Óvári & Shifman - Turkey
  8. Epipactis helleborine subsp. molochina Kreutz - Spain
  9. Epipactis helleborine subsp. neerlandica Buttler - Great Britain, Sweden, Belgium, Netherlands, France, Germany
  10. Epipactis helleborine subsp. orbicularis E.Klein - Austria, Czech Republic, Sweden, Germany, Switzerland, France, Spain, Italy, Baltic Republics
  11. Epipactis helleborine subsp. schubertiorum Kreutz - Italy
  12. Epipactis helleborine var. tangutica S.C.Chen & G.H.Zhu - China
  13. Epipactis helleborine subsp. tremolsii E.Klein - France, Spain, Portugal, Sardinia, Italy, Algeria, Morocco