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• Platanthera
• Platanthera dilatata

Platanthera dilatata — white northern bog-orchid

Facts

Northern bog-orchid is known to be pollinated by noctuid moths, although this observation was not made in New England. The Thompson Indians used this plant in sweatbaths for relief of rheumatic and other joint and muscle pains. They also used it as a wash for good luck.

Habitat

Alpine or subalpine zones, anthropogenic (man-made or disturbed habitats), bogs, cliffs, balds, or ledges, fens (calcium-rich wetlands), ridges or ledges, shores of rivers or lakes, swamps, wetland margins (edges of wetlands)

Characteristics

• Flowers

  Flower bract length

  Up to 40 mm

  Flower petal color

  white

  Flower symmetry

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

  Flowering date

  • August
  • July
  • June
  • September

  Flowers per inflorescence

  9–65

  Form of lower petal

  the labellum does not have a pouch-like shape

  Hairs on inflorescence axis

  the main stem of the inflorescence is hairless

  Inflorescence length

  100–300 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 flower stalk

  0 mm

  Length of narrowed base of lower petal

  0 mm

  Lobes at base of lower petal

  0 mm

  Lower petal characteristics

  • the labellum has spurs on it
  • the labellum is simple in form

  Lower petal length

  4–11 mm

  Lower petal outline

  the labellum is simple in form

  Lower petal strongly red-veined

  no

  Main color of lower petal

  white

  Nectar spur

  the flower has at least one nectar spur on it

  Nectar spur length

  4–12 mm

  Number of stamens

  1

  Pollen sacs

  the pollinia remain intact and do not fragment into smaller parts

  Self-pollinating flowers

  there are no cleistogamous flowers on this plant

  Sepals fused only to sepals

  the sepals are separate from one another

  Shape of viscidium

  • the viscidium is another shape than the choices given
  • the viscidium is long and narrow

  Spots on lower petal

  no

  Spur opening membrane

  there is no membrane over the spur opening

• 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 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

  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

  35–320 mm

  Leaf blade length to width ratio

  4.6–11.7

  Leaf blade shape

  • 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 oblong (rectangular but with rounded 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

  3–70 mm

  Leaves during flowering

  there are leaves on the plant when it is flowering

• Place

  Habitat

  • terrestrial
  • wetlands

  New England state

  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Vermont

  Specific habitat

  • alpine or subalpine zones
  • bogs
  • cliffs, balds, or ledges
  • edges of wetlands
  • fens (calcium-rich wetlands)
  • man-made or disturbed habitats
  • ridges or ledges
  • shores of rivers or lakes
  • 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