Calopogon oklahomensis D.H. Goldman

Oklahoma Grass Pink

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Accepted Synonym: Calopogon oklahomensis f. albiflorus

Calopogon oklahomensis, the Oklahoma Grass Pink, is distributed throughout the south central US. It can be distinguished from other Calopogon species by its relatively wide leaf that tends to be as long as or longer than the flowering stem, and the widely-spaced, pink to white, fragrant flowers that open nearly simultaneously. The lip of the non-resupinate flower is fiddle shaped with a rounded tip and a cluster of long, yellow tipped, stamen-like bristles. A second cluster of shorter pink bristles occur in the center of lip. C. oklahomensis prefers drier habitats such as prairies, pine savannas, flatwoods, and meadows, avoiding the wetter sites preferred by most other Calopogon species.

Calopogon oklahomensis is considered vulnerable and appears to have been extirpated from much of its historic range. Causes of this decline include the loss of prairie habits to agriculture and urbanization.


The flowers of Calopogon appear to be upside down with the lip at the top of the flower and use deception to attract pollinators. Midway up the lip, a tuft of orange-yellow hairs resembles pollen which attract naive, recently emerged bees expecting a reward. Bees of sufficient weight, force the hinged labellum to swing down, dropping the pollinator backwards onto the column. Any pollen attached to the bee is pressed onto the stigma and as the bee exits the flower, it picks up a new load of sticky pollen found on the end of the column.

Ecosystem Type

Bogs, disturbed habitats, grassland, marshes, prairie, savanna, woodlands


Leaf arrangement:
Number of leaves on stem:
  • one
  • two
Form of the labellum:
the labellum is not pouch-like
Main color of labellum:
  • blue to purple
  • pink to red
  • white
Nectar spur:
Inflorescence type:
the inflorescence is a raceme
Labellum length:
10–17 mm
Sepal length:
15–22 mm
Plant height:
15–36 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 Vulnerable
US Status N/A
Canadian Status N/A

North America Distribution

Adapted from USDA data