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• Spiranthes
• Spiranthes cernua

Spiranthes cernua — nodding ladies'-tresses

Facts

Nodding ladies'-tresses is one of the easiest native orchids to cultivate in the garden, if you can provide moist, boggy, acidic soils and partial shade. It can even be grown in containers. The flowers have a wonderful fragrance, and, as the common name suggests, may nod slightly in a breeze.

Habitat

Anthropogenic (man-made or disturbed habitats), fens (calcium-rich wetlands), forest edges, grassland, meadows and fields, ridges or ledges, wetland margins (edges of wetlands), woodlands

Characteristics

• Flowers

  Flower petal color

  • green
  • white
  • yellow

  Flower symmetry

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

  Flowering date

  • August
  • October
  • September

  Flowers per inflorescence

  1–40

  Form of lower petal

  the labellum does not have a pouch-like shape

  Hairs on inflorescence axis

  at least some of the hairs on the main stem of the inflorescence have glands

  Inflorescence length

  75–100 mm

  Inflorescence type

  the inflorescence is a spike (a long unbranched stem with flowers along it that lack stalks)

  Labellum position

  the labellum is in the lower position on the flower

  Length of narrowed base of lower petal

  0.3–0.8 mm

  Lobes at base of lower petal

  0 mm

  Lower petal characteristics

  the labellum is simple in form

  Lower petal length

  6–10.5 mm

  Lower petal outline

  the labellum is simple in form

  Lower petal strongly red-veined

  no

  Main color of lower petal

  • green to brown
  • white
  • yellow

  Nectar spur

  there are no nectar spurs on the flower

  Nectar spur length

  0 mm

  Number of stamens

  1

  Orientation of side petals

  • the lateral petals are angled steeply upwards
  • the lateral petals slant somewhat downward

  Pollen sacs

  the pollinia remain intact and do not fragment into smaller parts

  Self-pollinating flowers

  there are no cleistogamous flowers on this plant

  Sepal length

  6–12 mm

  Sepals fused only to sepals

  the sepals are separate from one another

  Shape of viscidium

  • the viscidium is lance-shaped (wider near one end, pointed at the ends)
  • the viscidium is long and narrow

  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

  • the plant has one or more swollen storage organs underground, such as bulbs, tubers or corms
  • there are only slender roots on the plant

• Leaves

  Bract relative length

  the bract is shorter than the associated flower

  Features of leaves

  the leaf does not have any of the mentioned special features

  Leaf arrangement

  • alternate: there is one leaf per node along the stem
  • the leaves are growing only at the base of the plant (basal)

  Leaf blade edges

  the edges of the leaf blade have no teeth

  Leaf blade length

  Up to 26 mm

  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 linear (very narrow with more or less parallel sides)
  • the leaf blade is oblanceolate (lance-shaped, but with the widest point above the middle of the leaf blade)
  • the leaf blade is obovate (egg-shaped, but with the widest point above the middle of the leaf blade)

  Leaf blade tip

  • the tip of the leaf blade is acuminate (tapers to a long, thin point)
  • the tip of the leaf blade is acute (sharply pointed)

  Leaf blade width

  Up to 20 mm

  Leaves during flowering

  • there are leaves on the plant when it is flowering
  • there are no leaves on the plant when it is flowering

  Number of leaves on stem

  one

• Place

  Habitat

  • terrestrial
  • wetlands

  New England state

  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont

  Specific habitat

  • edges of forests
  • edges of wetlands
  • fens (calcium-rich wetlands)
  • grasslands
  • man-made or disturbed habitats
  • meadows or fields
  • ridges or ledges
  • woodlands

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