Platanthera unalascensis (Spreng.) Kurtz

Alaska Orchid, Slender Spire Orchid

Facts About

Accepted Synonyms: Habenaria unalaschensis, Piperia unalascensis, Platanthera foetida, Spiranthes unalascensis

Platanthera unalascensis, commonly known as the Alaska Orchid is found from the Aleutians south to Baja California with disjunct populations in the Great Plains, Great Lakes area, and eastern Canada. This orchid grows up to 70 cm, usually with more than 6 stem bracts and basal leaves that wither before flowering. The slender spike has up to 100 loosely spaced, small yellowish green flowers. The petals are erect and sickle-shaped. The labellum is blunt with a fleshy central thickening. The nectar spur is stout and about as long as the labellum. It grows in various habitats including open mixed and coniferous forests, roadsides, tundra, outcrops, floodplains, thickets, and meadows. Plants in coastal populations may be shorter and more densely flowered. This orchid has a disagreeable ammonia-like smell.

Platanthera unalascensis is considered globally secure.


This orchid is pollinated by moths in the genera Eupithecia, Oidaematophorus and Platyptila with pollinaria attached to the proboscis.

Notes on Subspecies and Varieties

Ecosystem Type

Cliffs balds or ledges, floodplains, forests, meadows, shrublands or thickets, tundra


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:
green to brown
Nectar spur:
Inflorescence type:
the inflorescence is a spike
Labellum characteristics:
  • the labellum has a spur
  • the labellum is simple
Labellum length:
2–5 mm
Sepal length:
2–4 mm
Plant height:
Up to 75 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 Secure
US Status N/A
Canadian Status Secure

North America Distribution

Adapted from USDA data