Eastern Prairie Fringed Orchid (Platanthera leucophaea) - Threatened
The Eastern prairie fringed orchid is federally listed as threatened.
Species Description and Life History
One of 200 orchid species in North America, this member of genus Platanthera is identified by white, uniformly-colored, three-parted and conspicuously fringed labellum (lowermost petal). It can be distinguished from the closely related P. lacera by examination of the spur and lateral petals. P. leucophaea has a 2-4 cm spur and toothed lateral petals. P. lacera has a 1.4-2.1 cm long spur and entire lateral petals. This plant is 8 to 40 inches tall and has an upright leafy stem with a flower cluster called an inflorescence. The 3 to 8 inch lance-shaped leaves sheath the stem. Each plant has one single flower spike composed of 5 to 40 creamy white flowers.
This orchid is a perennial herb that grows from an underground tuber. Flowering begins from late June to early July, and lasts for 7 to 10 days. Blossoms often rise just above the height of the surrounding grasses and sedges. The more exposed flower clusters are more likely to be visited by the hawkmoth pollinators. Seed capsules mature over the growing season and are dispersed by the wind from late August through September. Plants may only flower once every few years. This is one of Maine’s rarest plants, and fewer than 20 plants are found each year.
Its habitat in Maine is the expansive Crystal Bog, actually a sphagnum-dominated fen fringed by white cedar and tamarack. Neighboring plants are sedges, bog birch, shrubby cinquefoil, bog laurel, sheep laurel and other sphagnum bog plants.
Threats in Maine include altered hydrology of the bog, invasive plant species, succession to woody vegetation, and foot traffic.
DistributionMaine’s single occurrence is in Crystal, Maine. The next closest populations are in Virginia and Michigan. Populations in New York, Pennsylvania, and New Jersey are believed to be extirpated. Because of its small, inconspicuous nature, it may yet be discovered elsewhere in Maine and the Northeast.