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• Cypripedium arietinum

Cypripedium arietinum — ram's-head lady's-slipper

Facts

The small but dramatic ram's-head lady's-slipper is rare and protected throughout New England. It flowers early, in mid May to early June, and flowers last only a week or so. Most individuals in a population do not flower in a given year.

Habitat

Forests, swamps

Characteristics

• Flowers

  Flower petal color

  • brown
  • green
  • red

  Flower symmetry

  there is only one way to evenly divide the flower (the flower is bilaterally symmetrical)

  Flowering date

  • June
  • May

  Flowers per inflorescence

  1–2

  Form of lower petal

  the labellum has a pouch-like shape

  Hairs on inflorescence axis

  • NA
  • at least some of the hairs on the main stem of the inflorescence have glands
  • the main stem of the inflorescence has hairs entirely without glands

  Inflorescence type

  the inflorescence has only one flower or a pair of flowers on it

  Labellum position

  the labellum is in the lower position on the flower

  Length of narrowed base of lower petal

  0 mm

  Lobes at base of lower petal

  0 mm

  Lower petal characteristics

  the labellum is in the shape of a pouch

  Lower petal length

  10–16 mm

  Lower petal outline

  the labellum is simple in form

  Lower petal strongly red-veined

  yes

  Main color of lower petal

  • green to brown
  • white

  Nectar spur

  there are no nectar spurs on the flower

  Nectar spur length

  0 mm

  Number of stamens

  2

  Orientation of side petals

  • the lateral petals slant outward
  • the lateral petals slant somewhat downward

  Pollen sacs

  NA

  Self-pollinating flowers

  there are no cleistogamous flowers on this plant

  Sepal length

  15–25 mm

  Sepals fused only to sepals

  the sepals are separate from one another

  Shape of viscidium

  NA

  Spots on lower petal

  no

  Spur opening membrane

  NA

  Spur opening shape

  NA

• Fruits or seeds

  Seed capsule orientation

  the capsule points upwards or is angled outwards

• Growth form

  Plant green or not

  the plant is chlorophyllous (it has green parts)

  Roots

  the rhizomes do not resemble coral

  Underground organs

  • there are only slender roots on the plant
  • this plant has a rhizome (a horizontal underground stem with roots growing from it)

• Leaves

  Bract relative length

  • the bract is longer than the associated flower
  • the bract is shorter than the associated flower

  Features of leaves

  • the leaf does not have any of the mentioned special features
  • the leaf is pleated or folded back and forth along its length

  Leaf arrangement

  alternate: there is one leaf per node along the stem

  Leaf blade edges

  the edges of the leaf blade have no teeth

  Leaf blade length

  50–110 mm

  Leaf blade length to width ratio

  3.1–3.8

  Leaf blade shape

  • the leaf blade is elliptic (widest near the middle and tapering at both ends)
  • the leaf blade is lanceolate (lance-shaped; widest below the middle and tapering at both ends)
  • the leaf blade is oblong (rectangular but with rounded ends)
  • the leaf blade is ovate (widest below the middle and broadly tapering at both ends)

  Leaf blade tip

  • the tip of the leaf blade is acute (sharply pointed)
  • the tip of the leaf blade is obtuse (bluntly pointed)

  Leaf blade width

  13–35 mm

  Leaves during flowering

  there are leaves on the plant when it is flowering

  Number of bracts on stem

  0

  Number of leaves on stem

  • five
  • four
  • three

• Place

  Habitat

  • terrestrial
  • wetlands

  New England state

  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Vermont

  Specific habitat

  • forests
  • swamps

Wetland status

Usually occurs in wetlands, but occasionally in non-wetlands. (Wetland indicator code: FACW)

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae