Cypripedium montanum Douglas ex Lindl.

Mountain Lady's Slipper

Facts About

Accepted Synonyms: Cypripedium occidentale

Cypripedium montanum, commonly known as the Mountain Lady's Slipper, is found in southeast Alaska to California, British Columbia, and east to Alberta, Montana and Wyoming. This lady’s slipper has one to three sweet-scented flowers with brownish purple sepals and petals. The petals are long, narrow and spirally twisted. The pouch-like labellum is white, faintly veined with purple toward the base, and spotted with purple inside the pouch. It grows in moderately moist to dry coniferous and deciduous forests, openings and thickets, around shrubs on open slopes, and subalpine meadows. It can be found in a wide range of sites, from shady to areas with full sun. The natural hybrid between Cypripedium montanum and Cypripedium parviflorum has been designated Cypripedium × columbianum.

Cypripedium montanum is apparently secure, although it is uncommon in portions of its range.

Pollination

This orchid is pollinated by small to medium sized bees in the families Andrenidae, Colletidae and Halictitidae foraging for nectar and pollen from flowering plants associated with the orchid. The fragrant flowers attract small bees, such as Lasioglossum but larger bumble bees are unable to fit into the flower. The smaller bees enter the flower and make their way to the back of the labellum, probably led by olfactory or visual cues. As they enter, they depress the elastic lip near the column base, creating a passageway that leads directly under the stigma and anthers toward one of two openings at the base of the column. As they make their exit through the small basal opening of the labellum, the sticky pollen is deposited on the dorsal side of their thorax or occasionally, the head.

Ecosystem Type

Alpine or subalpine zones, forests, meadows, shrublands or thickets, woodlands

Characteristics

Habitat:
terrestrial
Leaf arrangement:
alternate
Number of leaves on stem:
  • four
  • five
  • six
Form of the labellum:
the labellum is pouch-like
Labellum outline:
the labellum is simple
Main color of labellum:
white
Nectar spur:
absent
Inflorescence type:
the inflorescence has one flower or a pair of flowers
Labellum characteristics:
the labellum is saccate
Labellum length:
19–33 mm
Sepal length:
30–60 mm
Plant height:
25–71 cm
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Native to North America

Yes

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