ONH

  • 1060776
  • 1893
  • 1190180
  • P1600547
  • 1190142
  • 1690
  • 1685
  • 1825
  • DSCN7460
  • mobot31753000619673_0415
  • 1060776
    1 - Stream Orchid, or Giant Helleborine, Epipactis gigantea

    08/06/2008 Spruce Railroad Trail, Lake Crescent, WA

  • 1893
    2 - Stream Orchid flower.

    08/06/2008 Spruce Railroad Trail, Lake Crescent, WA

  • 1190180
    3 - Stream Orchid flower.

    08/06/2008 Spruce Railroad Trail, Lake Crescent, WA

  • P1600547
    4 - Stream Orchid.

    08/06/2008 Spruce Railroad Trail, Lake Crescent, WA

  • 1190142
    5 - Stream Orchid.

    07/02/2021 Spruce Railroad Trail, Lake Crescent, WA

  • 1690
    6 - A syrphid fly, Eupeodes volucris female, carries one Stream Orchid pollinarium toward a Stream Orchid flower.

    07/02/2021 Spruce Railroad Trail, Lake Crescent, WA

  • 1685
    7 - A syrphid fly, Eupeodes volucris female, with Stream Orchid pollinaria, on a Stream Orchid flower.

    07/02/2021 Spruce Railroad Trail, Lake Crescent, WA

  • 1825
    8 - A syrphid fly, Eupeodes volucris female, carries several Stream Orchid pollinaria toward a Stream Orchid flower.

    07/02/2021 Spruce Railroad Trail, Lake Crescent, WA

  • DSCN7460
    9 - A syrphid fly, Eupeodes volucris female, with several Stream Orchid pollinaria, on a Stream Orchid flower.

    07/02/2021 Spruce Railroad Trail, Lake Crescent, WA

  • mobot31753000619673_0415
    10 - Illustration of Stream Orchid, Epipactis gigantea from William Jackson Hooker’s Flora Boreali-Americana, 1839. https://www.biodiversitylibrary.org/page/415691

Stream Orchid, also called Giant Helleborine, Epipactis gigantea, grows in wet areas including lake margins, riverbanks, hot springs, and wet meadows in the western U.S.

This individual plant, which we have photographed in different years, is near the Spruce Railroad Trail on the west side of Lake Crescent in northwest Washington. The elevation is about 600 feet.

Some of these photos show syrphid flies carrying orchid pollen. Most orchids make sticky pollen-containing structures called pollinaria. When an insect contacts this structure, the structure breaks off the plant and sticks to the insect, which could carry it to another orchid. Slides 6-9 show pollinaria stuck to two different female syrphid flies.

 

Thanks to Bill Dean of bugguide for the syrphid fly identification.