Excerpts from Jim Conrad's
Naturalist Newsletter
page June 14, 2009 Newsletter, issued from the Siskiyou Mountains west of Grants Pass, Oregon:
WHITEFLOWER REIN ORCHID
Back East sometimes you run into lots of Ladies-Tresses Orchids so when I saw some here I didn't think much about it, just photographed one, which is shown above. It was easy to identify as a Spiranthes because the tiny flowers spiral around the very slender flower spike.
*UPDATE: In 2024 when I upload the above image to iNaturalist, I find that with my Eastern headset it may have been easy to recognize as a Ladies-Tresses, but it was wrong. iNaturalist user "arethusa" recognized our orchid as a West-Coast species I didn't know about, called the Whiteflower Rein Orchid, PLATANTHERA EPHEMERANTHA.
You may find other sources, such as the Flora of North America, currently referring to it as Piperia candida, but iNaturalist and Plants of the World Online currently regard that name as a synonym of Platanthera ephemerantha. Than name, by the way, was published first only back in 2009, when our picture was taken. The species occurs from southern Alaska south to coastal central California.