[https://goorchids.northamericanorchidcenter.org/] Range, Description, Habitat, Pollination: Platanthera transversa, the Flat Spurred Piperia, is widely distributed throughout California and extends northward into British Columbia. This orchid has a pair of basal leaves that emerge early in the spring but wither by the time of flowering. The inflorescence consists of numerous white to yellow flowers with green midveins on the sepals and petals and are fragrant at night. This orchid can be recognized by its slightly flattened horizontal spur more than twice as long as the labellum. P. transversa generally prefers dry sites, including scrub and oak woodlands or conifer forests.
Pollination
This orchid is pollinated by the moths in Geometridae such as Thallophaga taylorata with pollinaria attached to the proboscis. (link added by Mary Ann Machi)
Calflora:
Information on California plants for education, research and conservation,
with data contributed by
public and private institutions and individuals.
[web application]. 2025.The Calflora Database
[a non-profit organization].Available:
https://www.calflora.org/(Accessed: 03/29/2025).