Large Yellow Lady's Slipper

(Cypripedium pubescens)

Large Yellow Lady's Slipper (Cypripedium pubescens Willd.)

Identification: Flower yellow, large. Lower petals forming a hollow, pouchlike structure (slipper). Slipper about 2 inches long. Two lateral "petals" elongate and twisted, upper "petal" wider, slightly arched over the flower. Flower solitary at the top of the plant. Stem with a single green leaf somewhat overhanging the flower. A pair of large, ovate-elongate leaves at the base of the plant. Plant 1.5 to 2 feet in height.

Distribution: Throughout most of North America except for the southern United States.

Habitat: Large Yellow Lady's Slipper is found in bogs, swamps, and rich woods.

Flowering period: April to August.

Similar Species: Small Yellow Lady's Slipper (see picture below) is very similar to Large Yellow Lady's Slipper. The slipper is smaller (about 0.75 to 1.5 inches in length. The upper "petals" (sepals) are darker and browner than those of Large Yellow Lady's Slipper. Small Yellow Lady's Slipper is found primarily on limestone derived soils.