Calypso bulbosa — fairy-slipper
![Plant form: Calypso bulbosa. ~ By Ben Legler. ~ Copyright © 2024 Ben Legler. ~ mountainmarmot[at]hotmail.com ~ U. of Washington - WTU - Herbarium - biology.burke.washington.edu/herbarium/imagecollection.php](https://newfs.s3.amazonaws.com/taxon-images-1000s1000/Orchidaceae/calypso-bulbosa-americana-ha-blegler.jpg)
![Leaves: Calypso bulbosa. ~ By Robert Buchsbaum. ~ Copyright © 2024 Robert Buchsbaum. ~ rbuchsbaum[at]massaudubon.org](https://newfs.s3.amazonaws.com/taxon-images-1000s1000/Orchidaceae/calypso-bulbosa-le-rbuchsbaum.jpg)
![Inflorescences: Calypso bulbosa. ~ By Robert Buchsbaum. ~ Copyright © 2024 Robert Buchsbaum. ~ rbuchsbaum[at]massaudubon.org](https://newfs.s3.amazonaws.com/taxon-images-1000s1000/Orchidaceae/calypso-bulbosa-in-rbuchsbaum.jpg)
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Facts
Fairy-slipper is a rare orchid in New England, being found only in northern white-cedar (Thuja occidentalis) dominated swamps in Maine, New Hampshire and Vermont. The generic name (Calypso) comes from Homer's sea-nymph in the Odyssey who kept Odysseus concealed seven years on her island. The Thompson Indians of British Columbia chewed the corms and sucked on the flowers to treat mild epilepsy.
Habitat
Swamps
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.
enlargeCharacteristics
- Habitat
- wetlands
- New England state
-
- Maine
- New Hampshire
- Vermont
- Leaf arrangement
- basal: the leaves are growing only at the base of the plant
- Number of leaves on stem
- absent
- Form of lower petal
- the labellum has a pouch-like shape
- Lower petal outline
- the labellum is lobed but not fringed
- Main color of lower petal
-
- pink to red
- white
- Nectar spur
- there are no nectar spurs on the flower
- Inflorescence type
- the inflorescence has only one flower or a pair of flowers on it
- Lower petal characteristics
-
- the labellum is in the shape of a pouch
- the labellum is lobed
- Lower petal length
- 13–23 mm
- Sepal length
- 10–24 mm
-
Flowers
- Flower petal color
-
- purple
- white
- 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 flower stalk
- NA
- Hairs on inflorescence axis
- NA
- Inflorescence length
- 35–50 mm
- Inflorescence type
- the inflorescence has only one flower or a pair of flowers on it
- Inflorescence width
- 30–40 mm
- Labellum position
- the labellum is in the lower position on the flower
- Length of narrowed base of lower petal
- 0 mm
- Length of peduncle
- 100–200 mm
- Lobes at base of lower petal
- 0 mm
- Lower petal characteristics
-
- the labellum is in the shape of a pouch
- the labellum is lobed
- Lower petal length
- 13–23 mm
- Lower petal outline
- the labellum is lobed but not fringed
- Lower petal strongly red-veined
- no
- Main color of lower petal
-
- pink to red
- white
- 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
- Self-pollinating flowers
- there are no cleistogamous flowers on this plant
- Sepal length
- 10–24 mm
- Sepals fused only to sepals
- the sepals are separate from one another
- Shape of viscidium
- the viscidium is another shape than the choices given
- Spots on lower petal
- yes
- Spur opening membrane
- NA
- Spur opening shape
- NA
-
Fruits or seeds
- Fruit length
- 20–30 mm
- Fruit width
- 10–15 mm
- Length of peduncle when in fruit
- 0 mm
- 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 are branched and 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 is pleated or folded back and forth along its length
- Leaf arrangement
- basal: the leaves are growing only at the base of the plant
- Leaf blade edges
- the edges of the leaf blade have no teeth
- Leaf blade length
- 10–65 mm
- Leaf blade length to width ratio
- 0.8–1.3
- Leaf blade shape
-
- the leaf blade is elliptic (widest near the middle and tapering at both ends)
- the leaf blade is orbicular (roughly circular, as wide as long)
- 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 acuminate (tapers to a long, thin point)
- the tip of the leaf blade is acute (sharply pointed)
- the tip of the leaf blade is obtuse (bluntly pointed)
- Leaf blade width
- 12–52 mm
- Leaves during flowering
- there are leaves on the plant when it is flowering
- Number of bracts on stem
- 2–3
- Number of leaves on stem
- absent
-
Place
- Habitat
- wetlands
- New England state
-
- Maine
- New Hampshire
- Vermont
- Specific habitat
- swamps
Wetland status
Usually occurs in wetlands, but occasionally in non-wetlands. (Wetland indicator code: FACW)
In New England
Distribution
- Connecticut
- absent
- Maine
- present
- Massachusetts
- absent
- 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.
- Maine
- uncommon to fairly widespread (S-rank: S3S4)
ssp. americana
- New Hampshire
- historical (S-rank: SH), endangered (code: E)
var. americana
- Vermont
- extremely rare (S-rank: S1), threatened (code: T)
Subspecies and varieties
Our subspecies is ssp. americanus (R. Br. ex Ait. f.) A. Haines
From Flora Novae Angliae dichotomous key
1. Calypso bulbosa (L.) Oakes ssp. americana (R. Br. ex Ait. f. ) A. Haines NC
fairy-slipper. Calypso bulbosa (L.) Oakes var. americana (R. Br. ex Ait. f.) Luer; Cypripedium bulbosum L., pro parte; Cytherea bulbosa (L.) House, pro parte • ME, NH, VT. Evergreen swamps dominated by Thuja occidentalis.
Native to North America?
Yes
Sometimes confused with
- Cypripedium acaule:
- labellum lacking a pair of apical horns and also without evident yellow bristles, and plants with a pair of basal leaves (vs. C. bulbosa, with labellum with a pair of yellow, apical horns and also with evident, yellow bristles, and plants with a single basal leaf).
- Cypripedium arietinum:
- labellum lacking a pair of apical horns and also without evident yellow bristles, and plants with 3 or 4 leaves borne on a stem (vs. C. bulbosa, with labellum with a pair of yellow, apical horns and also with evident, yellow bristles, and plants with single basal leaf).
Synonyms
- Calypso bulbosa (L.) Oakes var. americana (R. Br. ex Ait. f.) Luer