Isotria medeoloides (Pursh) Raf.

Small Whorled Pogonia

Facts About

Accepted Synonyms: Arethusa medeoloides, Pogonia affinis, Odonectis affinis

Isotria medeoloides, also known as Small Whorled Pogonia, is found primarily in eastern Canada and the United States, with a few populations in central U.S. states. It produces 4-6 greyish green leaves which form a whorled ring around the upper part of the stem. Its flowers are pale green, with the labellum often colored light yellow to pale green or white, usually streaked with green. It grows in forests and woodlands, generally preferring young, open-canopy forests and disappearing from more mature forests where the canopy is thicker.

Isotria medeoloides is globally considered imperiled, with most of the world's population occurring in Maine and New Hampshire. It is considered rare, imperiled, or extirpated in every state in which it has been reported. It can be distinguished from I. verticillata by its sepals, which are green instead of purple.


This orchid is autogamous and does not need a pollinator for reproduction. Shortly after the flower opens, pollen emerges out of the anther and comes in contact with the stigma.

Ecosystem Type

Disturbed habitats, forests, woodlands


Leaf arrangement:
Number of leaves on stem:
  • four
  • five
  • six
Form of the labellum:
the labellum is not pouch-like
Labellum outline:
the labellum is lobed
Main color of labellum:
  • green to brown
  • white
  • yellow
Nectar spur:
Inflorescence type:
the inflorescence has one flower or a pair of flowers
Labellum characteristics:
the labellum is lobed
Labellum length:
11–16 mm
Sepal length:
12–25 mm
Plant height:
4–25 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 Imperiled
US Status Listed Threatened
Canadian Status Endangered

North America Distribution

Adapted from USDA data