Cypripedium passerinum : White Ladys Slipper


Scientific Name:

Kingdom: Plantae


Class: Monocoteldonae (one seed-leaf)

Family: Orchidaceae (Orchid Family)

Genera: Cypripedium (Lady's Slipper) (Gk. Kypris=Venus, godess of love + podion=a slipper, referring to the shape of the flower)

Species: passerinum (Lat. passer=sparrow, referring to the slight resemblence of the flower to a sparrows egg)

English Name(s):

White Ladys Slipper, Northern, or Sparrows Egg Lady's Slipper

First Nation Names:



  • Stems leafy, 10-35 cm high pubescent (hairy).


  • 3-5 alternate leaves, 5-16cm long. Sticky pubescent (hairy). on both sides.

Reproductive Parts:

  • Flowers perfect (bisexual). Zygomorphic (biliteral symmetry).
  • Petals 3 of which the side two are alike but are different from the lower one which is lip like.
  • Sepals 3.
  • Column (fused filaments and style) with 2 anthers (male parts).
  • Lateral petals long, linear. Lower petal (lip) inflated, sac or slipper like.
  • Flowers 1-3, small, fragrant.
  • Lateral petals white, linear-elliptic to oblong in shape. And about as long as the lip.
  • Lateral Sepals about 1.5cm long, free almost to base, pubescent (hairy) on the lower surface.
  • Lower petal (lip)1.5-2cm long, egg-shaped, pure white, but so translucent that purple spots on the inner surface are faintly visible.


  • Fruit a three chambered capsule containing innumerable minute seeds.
  • Capsule 2-3cm long, erect, pubescent (hairy) elliptical to obovate in shape.
  • Each capsule produces 10,400 to 26,500 seeds.

Not to Be Confused With:



    • Herbacious.
    • The flowers have only 2 anthers (male parts) which is concidered a primitive charactaristic in the Orchid Family.

    Life Cycle:

    • Perennial.
    • Blooming occurs after 2-3 years of growth.

    Seasonal Cycle:


    Animal Uses:

    • The 'Slipper' is an insect trap. It is easy for insects to enter the slipper but the smooth surface makes it hard to escape. There is a strip of hairs at the 'heel' of the slipper which an insect can climb up and out of the flower.
    • When escaping the flower, the insect has to come incontact with first the pistle (female part), where it can deposit any pollin from other flowers, and then the anthers (male part), where it can pick up new pollen to take to another flower.


    • Mossy woods, lake margins, heathlands.




    • Caution: The leaves are known to cause irritation of the skin.
    • Plants are grown in gardens. They can be divided and transplanted in early spring, if garden conditions closely resemble those of its natural habitat.
    • Propogation is done by division. Each year 3-8 shoots are produced and 1-3 of these can be removed in the spring. Divisions should have roots and be planted in coniferous humus and woodchips.



        Traditional Gwich'in:





                Traditional Other:




                    • Cypripedin a powder produced by precipitating the tincture with water was said to have greater powers than the root and was given to children instead of opium.
                    • Plants in this genus were known for the drug Cypripedium which was used as a gentle nervous stimulant or antispasmodic.
                    • Plants taken in a sweetened concoction for headache.
                    • Roots were chewed as a sedative especially during menstruation and childbirth.



                      Flower front-view

                      Flower side-view

                      Plant top-view

                      Capsules from 4 different seasons

                      Leaves sprouting

                      Illustration from: Illustrated Flora of BC

                      Range Maps

                      World Range: Boreal NA from AK to James Bay; Disjunct populations on north shore of Lake Superior and Mingan Isla

                      Prov/State Abrev. List

                      In Yukon: Found throughout the territory save for the north slope and the Liard River Basin.

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