Cypripedium passerinum
Cypripedium passerinum is a species of lady's slipper orchid known by the common names sparrow's-egg lady's-slipper, spotted lady's-slipper, and Franklin's lady's-slipper.
Description
This orchid is a rhizomatous monocot, perennial herb growing to a maximum height around. There are 3 to 7 oval or lance-shaped leaves arranged alternately on the stem, each up to long by wide. The herbage is hairy and sticky. The inflorescence at the top of the stem contains one or two flowers. The flower has a dorsal sepal covering the petals and two lateral sepals. There are three petals: two flat white petals on either side and one central petal modified into a white or pink-tinged pouch with purplish spotting at the lip and inside, which is said to resemble a sparrow's egg. The fruit is a capsule. The plant may reproduce by seed but it more often reproduces vegetatively by sending up more stems from the rhizome.
Habitat
This species grows farther north than other Cypripedium. It grows in moist spruce forests at low elevations, tundra, dunes, and river terraces, lakeshores, and streambanks. It often grows on calcareous substrates. It is associated with plants such as white spruce, Engelmann spruce, western redcedar, red-osier dogwood, willows, horsetail, longtube twinflower, sedges, one-sided pyrola, and moss carpet.
Range
Cypripedium passerinum is native to northern North America. It is widespread in Canada from British Columbia to Quebec, as well as all three northern territories. It also is found Alaska and in the Rocky Mountains of Montana, including inside Glacier National Park.
Importance to the ecosystem
Little is known about the importance of C. passerinum to the ecosystem. In some studies, it has been noted that insects have fed on them. Bees have been identified to pollinate other Cypripedium however unlike other Cypripedium, C. passerinum is self pollinating and therefore does not require a pollinator for reproduction. A variety of species grow with the sparrow's-egg lady-slipper, such as Linnaea borealis, Carex concinna, Orthilia secunda, and ''Pleurozium schreberi.''
Conservation
Cypripedium passerinum is an extremely rare plant in certain areas. Its highly specific habitat requirements contribute to its risk of extinction. In the United States, C. passerinum is only found in two states, Alaska and Montana, and in locations that are threatened by oil and gas exploration. In Canada, it has been found in Wagner Natural Area outside of Edmonton, where efforts are ongoing to use microsatellites for its conservation.