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- Platanthera
- Platanthera dilatata
Platanthera dilatata — white northern bog-orchid
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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)
New England distribution
Adapted from BONAP data
Native: indigenous.
Non-native: introduced (intentionally or unintentionally); has become naturalized.
County documented: documented to exist in the county by evidence (herbarium specimen, photograph). Also covers those considered historical (not seen in 20 years).
State documented: documented to exist in the state, but not documented to a county within the state. Also covers those considered historical (not seen in 20 years).
Note: when native and non-native populations both exist in a county, only native status is shown on the map.
Found this plant? Take a photo and post a sighting.
Characteristics
- Habitat
-
- terrestrial
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Vermont
- Leaf arrangement
- alternate: there is one leaf per node along the stem
- Form of lower petal
- the labellum does not have a pouch-like shape
- Lower petal outline
- the labellum is simple in form
- Main color of lower petal
- white
- Nectar spur
- the flower has at least one nectar spur on it
- Inflorescence type
- the inflorescence is a spike (a long unbranched stem with flowers along it that lack stalks)
- Lower petal characteristics
-
- the labellum has spurs on it
- the labellum is simple in form
- Lower petal length
- 4–11 mm
-
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)
In New England
Distribution
- Connecticut
- present
- Maine
- present
- Massachusetts
- present
- New Hampshire
- present
- Rhode Island
- absent
- Vermont
- present
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Connecticut
- historical (S-rank: SH), special concern, extirpated (code: SC*)
- Massachusetts
- rare (S-rank: S2), threatened (code: T)
var. dilatata
- Massachusetts
- unranked (S-rank: SNR)
Subspecies and varieties
Our variety is Platanthera dilatata (Pursh) Lindl. ex Beck var. dilatata.
From Flora Novae Angliae dichotomous key
6. Platanthera dilatata (Pursh) Lindl. ex Beck var. dilatata N
white northern bog-orchid. Habenaria dilatata (Pursh) Hook.; Limnorchis dilatata (Pursh) Rydb. • MA, ME, NH, VT. Bogs, fens, wet openings in boreal and subalpine forests, river shores, bases of wet, high-elevation cliffs, ditches.
Native to North America?
Yes
Synonyms
- Habenaria dilatata (Pursh) Hook.
- Limnorchis dilatata (Pursh) Rydb.