Yellow Lady’s Slipper (Cypripedium parviflorum)

 

Yellow Lady’s Slipper (Cypripedium parviflorum)

photo by Carla Wells

Yellow lady slipper’s pouch‑shaped blossom isn’t just ornamental—it’s a specialized pollinator trap. Small bees, often Andrena mining bees, slip inside while searching for nectar, even though the flower offers none, and end up navigating the narrow, light‑guided tunnel that forces them past the stigma and anthers on their way out. That brief moment of confusion is the orchid’s entire reproductive strategy, and it works only in places where the surrounding woodland community is intact enough to support both the bees and the soil fungi the plant depends on to germinate.

By late May the flowers begin to appear, rising anywhere from four to 24 inches above the forest floor. Each one carries a single, inflated yellow petal two to three inches high, framed by two brownish‑purple petals and two brownish‑purple sepals. The basal leaves stretch up to eight inches long, their deep parallel veins catching the angled light of wet deciduous woods, while smaller stem leaves alternate and clasp the stem. You find the plant in shady swamps, bogs, and cool, saturated woodlands—places where filtered light, steady moisture, and undisturbed leaf litter give both the orchid and its fungal partners the conditions they need.

Sources: 

USDA Forest Service – Cypripedium parviflorum (Yellow Lady’s Slipper)

Minnesota Wildflowers – Yellow Lady’s Slipper (Cypripedium parviflorum)

Illinois Wildflowers – Yellow Lady’s Slipper Orchid

Lady Bird Johnson Wildflower Center – Cypripedium parviflorum

Wisconsin DNR – Wisconsin Native Orchids: Yellow Lady’s Slipper

North American Orchid Conservation Center – Pollination and Mycorrhizal Ecology of Lady’s Slippers

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