Platanthera transversa (Suksd.) R.M.Bateman

Flat Spurred Piperia

Facts About

Accepted Synonym: Piperia transversa.

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.

Platanthera transversa is apparently secure across its range with many sites occurring in protected parks and reserves.


This orchid is pollinated by the moths in Geometridae such as Thallophaga taylorata with pollinaria attached to the proboscis.

Ecosystem Type

Forests, shrublands or thickets, woodlands


Leaf arrangement:
Number of leaves on stem:
Form of the labellum:
the labellum is not pouch-like
Labellum outline:
the labellum is simple
Main color of labellum:
  • white
  • yellow
Nectar spur:
Inflorescence type:
the inflorescence is a spike
Labellum characteristics:
the labellum is simple
Labellum length:
2.2–5.3 mm
Sepal length:
2.5–4.5 mm
Plant height:
12–57 cm
Show All Characteristics

Native to North America


North American Conservation Status & Distribution

Conservation Status

Select a location to view conservation status:

Conservation and Wetland Status
Global Rank Apparently Secure
US Status N/A
Canadian Status Secure

North America Distribution

Adapted from USDA data