Regularity: Regularly occurring
Regularity: Regularly occurring
Global Range: Circumboreal species; Labrador to Alaska, south to Maine, Michigan, New York, west into the Rockies, Arizona and California, also in Europe.
Fairy slipper has a circumboreal distribution. In North America, it occurs extensively across the United States and Canada, ranging from Alaska east to Newfoundland and south to California, New Mexico, and Michigan. Historic populations in New York and New Hampshire have been extirpated . The Flora of North America. provides a distributional map for fairy slipper.
Calypso bulbosa var. americana occurs throughout most of the general distribution of the species, except in Idaho, Oregon, and California. Calypso bulbosa var. occidentalis occurs in Montana, Idaho, Washington, Oregon, California, Alaska, and British Columbia .
States or Provinces
Regional Distribution in the Western United States
This species can be found in the following regions of the western United States (according to the Bureau of Land Management classification of Physiographic Regions of the western United States):
BLM PHYSIOGRAPHIC REGIONS :
1 Northern Pacific Border
2 Cascade Mountains
3 Southern Pacific Border
4 Sierra Mountains
5 Columbia Plateau
8 Northern Rocky Mountains
9 Middle Rocky Mountains
11 Southern Rocky Mountains
12 Colorado Plateau
15 Black Hills Uplift
This description provides characteristics of the fairy slipper that may be relevant to its fire ecology, and is not meant for identification. Keys for identification are available [20,21,30,37,39,43,56,73].
Fairy slipper is a native, perennial forb. It has a single, basal green leaf that is 1 to 2 inches (3-6 cm) long. The flower is usually solitary (rarely with 2 flowers), with a long, scoop-shaped lip tufted, 3 erect-spreading sepals, and 2 petals that are narrow, pointed and twisted. The fruits are erect capsules. The erect stem stands between 2 to 8 inches (5-20 cm) tall, extending from a bulb-like corm [26,57,59]. Fibrous roots are typically produced at the base of a single corm .
Most often found in cool, mature cedar swamps or on slopes of mixed coniferous growth underlain by some type of calcareous bedrock. At all known Maine stations but one, CALYPSO is associated with northern white cedar (THUJA OCCIDENTALIS). In the Rockies, CALYPSO prefers dry coniferous slopes. This element prefers moderate to well-drained sites with little herbaceous competition, wherever it grows - even in THUJA swamps it is usually found growing up on ridges, cedar butts, upon decaying logs or on gentle slopes.
Key Plant Community Associations
The fairy slipper is not documented as a dominant or an indicator species in
vegetation types for the United States and Canada. Vegetation classifications
describing plant communities where fairy slipper a component species follow:
AZ and NM: Fir-spruce (Abies-Picea spp.) and mixed-conifer forests 
ID: Western larch-Douglas-fir (Larix occidentalis-Pseudotsuga menziesii) forests, Priest River Experimental Forest 
MT: Engelmann spruce/sweet-scented bedstraw (Picea engelmannii/Galium triflorum)
subalpine fir/red baneberry (Abies lasiocarpa/Actaea rubra) habitat types 
WY: Jackson Hole Wildlife Park Â Fir-spruce and
lodgepole pine (Pinus contorta) habitats 
WA: Mt. Rainier National Park: Pacific silver fir/dwarf Oregon-grape (Abies amabilis/Berberis nervosa) habitat type
Pacific silver fir/devil's club (Oplopanax horridus) habitat type 
Olympic National Park: coniferous
forest plant associations 
OR: Cascade Range white fir (Abies concolor) series with
constancy values ranging
western hemlock (Tsuga heterophylla)
Cascade Range series at 2% constancy 
Siskiyou Mountain Province: Tanoak (Lithocarpus densiflorus)
Willamette and Siuslaw National Forests: western hemlock series [34,35].
Grand fir (Abies grandis) series
Douglas-fir associations on the Willamette National Forest .
Willamette Valley Â Douglas-fir forests 
Common understory associates of fairy slipper
include western yarrow (Achillea
millefolium), red besseya (Besseya rubra), wild hyacinth (Triteleia
hyacinthina), glacier lily (Erythronium grandiflorum), wild strawberry
(Fragaria spp.), queencup beadlily (Clintonia uniflora), northern
bedstraw (Galium boreal), sweet-scented bedstraw (Galium triflorum),
heartleaf arnica (Arnica cordifolia), American trailplant (Adenocaulon
bicolor), Piper's anemone (Anemone piperi), large-leaf sandwort (Moehringia
macrophylla), Idaho goldthread (Coptis occidentalis), Oregon fairybell (Disporum
spp.), rattlesnake plantain (Goodyera
oblongifolia), western starflower (Trientalis
sp.), twinflower (Linnaea borealis), and starry Solomon-seal (Maianthemum
Habitat: Rangeland Cover Types
This species is known to occur in association with the following Rangeland Cover Types (as classified by the Society for Range Management, SRM):
More info for the term: cover
SRM (RANGELAND) COVER TYPES :
409 Tall forb
411 Aspen woodland
920 White spruce-paper birch
Habitat: Cover Types
This species is known to occur in association with the following cover types (as classified by the Society of American Foresters):
More info for the term: cover
SAF COVER TYPES :
5 Balsam fir
12 Black spruce
13 Black spruce-tamarack
30 Red spruce-yellow birch
32 Red spruce
33 Red spruce-balsam fir
37 Northern white-cedar
39 Black ash-American elm-red maple
107 White spruce
108 Red maple
201 White spruce
203 Balsam poplar
204 Black spruce
205 Mountain hemlock
206 Engelmann spruce-subalpine fir
210 Interior Douglas-fir
211 White fir
212 Western larch
213 Grand fir
215 Western white pine
218 Lodgepole pine
223 Sitka spruce
224 Western hemlock
225 Western hemlock-Sitka spruce
226 Coastal true fir-hemlock
227 Western redcedar-western hemlock
228 Western redcedar
229 Pacific Douglas-fir
230 Douglas-fir-western hemlock
234 Douglas-fir-tanoak-Pacific madrone
237 Interior ponderosa pine
243 Sierra Nevada mixed conifer
244 Pacific ponderosa pine-Douglas-fir
253 Black spruce-white spruce
Habitat: Plant Associations
This species is known to occur in association with the following plant community types (as classified by Küchler 1964):
More info for the term: bog
KUCHLER  PLANT ASSOCIATIONS:
K001 Spruce-cedar-hemlock forest
K002 Cedar-hemlock-Douglas-fir forest
K003 Silver fir-Douglas-fir forest
K004 Fir-hemlock forest
K005 Mixed conifer forest
K006 Redwood forest
K008 Lodgepole pine-subalpine forest
K011 Western ponderosa forest
K012 Douglas-fir forest
K013 Cedar-hemlock-pine forest
K014 Grand fir-Douglas-fir forest
K015 Western spruce-fir forest
K017 Black Hills pine forest
K018 Pine-Douglas-fir forest
K020 Spruce-fir-Douglas-fir forest
K021 Southwestern spruce-fir forest
K029 California mixed evergreen forest
K093 Great Lakes spruce-fir forest
K094 Conifer bog
K096 Northeastern spruce-fir forest
This species is known to occur in the following ecosystem types (as named by the U.S. Forest Service in their Forest and Range Ecosystem [FRES] Type classification):
FRES10 White-red-jack pine
FRES21 Ponderosa pine
FRES22 Western white pine
FRES24 Hemlock-Sitka spruce
FRES26 Lodgepole pine
|Arizona||8,500 to 10,000 feet (2,590-3,048 m) |
|California||<5,900 feet (<1,800 m) |
|Colorado||7,000 to 10,000 feet (2,134-3,048 m) |
|New Mexico||7,000 to 10,000 feet (2,134-3,048 m) |
|Utah||8,900 to 10,500 feet (2,700-3,200 m) |
|Pacific Northwest (including British Columbia and Alaska)||sea level to mid-montane elevations [39,59]|
|Pryor Mountains (south-central Montana)||5,900 to 8,500 feet (1,800-2,600 m) |
|Alberta||1,600 to 5,200 feet (500-1,600 m) |
Number of Occurrences
Note: For many non-migratory species, occurrences are roughly equivalent to populations.
Estimated Number of Occurrences: 81 to >300
Comments: More than a hundred occurrences seen in Michigan alone.
CALYPSO grows primarily in the fall and early spring, blooming from late May to late June (Mousely 1924). The evergreen, solitary leaf, emerges in late August, overwinters, and shrivels soon after blooming. Capsules are set in June and July, and soon after there may be no visible signs of of this species. The new overwintering leaves usually begin to emerge in September (Caljouw 1981), but Vickery and Rooney (pers. observation) noted emerging leaves in mid August in Lee, Maine. Very few plants set fruit (Mosquin 1970). However, fairy slipper orchids produce thousands of seeds per capsule, which gives them the potential of good spread by seed.
Mousely (1924) reports that principal reproduction is by rhizomatous roots at the base of the tubers. Another factor contributing to the elusive qualities of this species is dormancy, one to several year periods being common (pers. obs.). Densities of this species vary from the usual one or two to the up to fifty plants per square foot reported by some references (Rooney, Gawler, Merry, Vickery pers. comm., Mosquin 1970). In Crystal Bog Preserve the population has fluctuated from one flowering plant in 1979 upwards to 12 blooming in spring of 1981; down to five flowers in spring of 1982. In fall of 1983 Mckellar & Rooney counted 40 sterile leaves and five plants with flower buds.
CALYPSO apparently is intolerant of soil temperatures in excess of 15 degrees C and of canopy cover less than 60% (Caljouw 1981). It is principally associated with THUJA OCCIDENTALIS - growing in the shaded duff with little or no herbaceous competition.
In several sites in Maine, the cover has been extensively damaged by spruce budworm recently, allowing light to penetrate to the forest floor. The spring of 1983 marked the lowest population of CALYPSO at these sites since its discovery in 1979 (Rooney). The decline of flowering plants probably reflects the damage done to the cover by the budworm and perhaps frost damage to the tubers. The winter of '82/'83 was distinguished by the absence of the usual protective blanket of snow.
Fire Management Considerations
To date (2006), there is no research providing management recommendations regarding fairy slipper. Prescribed fire should be used cautiously when protecting or promoting fairy slipper is a fire management objective. Small-scale burning, fuel evaluation, and population monitoring after prescribed and wildfires can help manager access effects of fire to fairy slippers in their area.
Plant Response to Fire
Fairy slipper probably sprouts from the corm after top-kill. Corms are generally well protected from fire, so fairy slipper's response to fire is likely similar to that of other geophytes: sprouting after minimal fire damage . The postfire response, however, is largely dependent on the depth of the corm in the soil, the soil temperatures reached during the fire, and temperature duration . Sustained, severe ground fire may damage or kill fairy slipper. Postfire response may also depend on the degree in which the habitat of fairy slipper changes. Since fairy slipper does best in shady, moist conditions, it may not be able to thrive on early successional sites where shade and litter have been removed by fire.
Immediate Effect of Fire
POSTFIRE REGENERATION STRATEGY :
Geophyte, growing points deep in soil
Fire adaptations: To date (2006), published information on fairy slipper response to fire is lacking. Given that the perennating part of the fairy slipper is a corm and that corms are generally well protected, fairy slipper is probably well adapted to survive most fires . Its ability to regenerate from seed after fire is undocumented. Case's  anecdotal statement that fairy slipper does not occur on mineral soil suggests that fairy slipper does not occur in early postfire succession; however, is it possible that fairy slipper has a seed bank [1,75] and establishes from seed in later postfire succession. Research is needed on fairy slipper's fire ecology.
FIRE REGIMES: Fairy slipper occurs in a wide range of FIRE REGIMES, varying from very infrequent, stand-replacement fire in eastern spruce-fir communities  to short-return interval surface fire in ponderosa pine forests of the western United States . The cool and moist site characteristics of communities where fairy slipper is most frequent, such as western hemlock, Pacific silver fir, white fir, and high-elevation subalpine fir, suggest that infrequent, stand-replacing fires are most common in fairy slipper habitats.
The following table provides fire return intervals for plant communities and ecosystems where fairy slipper is important. It may not be inclusive. For further information, see the complete FEIS fire regime table.
|Community or Ecosystem||Dominant Species||Fire Return Interval Range (years)|
|silver fir-Douglas-fir||Abies amabilis-Pseudotsuga menziesii var. menziesii||>200|
|grand fir||Abies grandis||35-200 |
|tamarack||Larix laricina||35-200 |
|western larch||Larix occidentalis||25-350 [3,10,19]|
|Great Lakes spruce-fir||Picea-Abies spp.||35 to >200|
|northeastern spruce-fir||Picea-Abies spp.||35-200 |
|Engelmann spruce-subalpine fir||Picea engelmannii-Abies lasiocarpa||35 to >200 |
|black spruce||Picea mariana||35-200|
|conifer bog*||Picea mariana-Larix laricina||35-200|
|red spruce*||Picea rubens||35-200 |
|Rocky Mountain lodgepole pine*||Pinus contorta var. latifolia||25-340 [9,10,69]|
|Sierra lodgepole pine*||Pinus contorta var. murrayana||35-200|
|western white pine*||Pinus monticola||50-200|
|Pacific ponderosa pine*||Pinus ponderosa var. ponderosa||1-47 |
|interior ponderosa pine*||Pinus ponderosa var. scopulorum||2-30 [2,8,49]|
|Rocky Mountain Douglas-fir*||Pseudotsuga menziesii var. glauca||25-100 [2,4,5]|
|coastal Douglas-fir*||Pseudotsuga menziesii var. menziesii||40-240 [2,54,63]|
|California mixed evergreen||Pseudotsuga menziesii var. menziesii-Lithocarpus densiflorus-Arbutus menziesii||<35 |
|redwood||Sequoia sempervirens||5-200 [2,24,68]|
|western redcedar-western hemlock||Thuja plicata-Tsuga heterophylla||>200|
|western hemlock-Sitka spruce||Tsuga heterophylla-Picea sitchensis||>200|
|mountain hemlock*||Tsuga mertensiana||35 to >200 |
More info for the term: succession
Fairy slipper occurs in all stages of succession. It is listed as a "preclimax" species found in streambottoms of the Selway-Bitterroot Wilderness of Idaho and Montana . In the boreal forests of central Alaska, fairy slipper is found in mature successional stages starting in Stage 7 (as described by Van Cleve and Viereck ), which is predominantly mature balsam poplar (Populus balsamifera spp. balsamifera) and young white spruce (Picea glauca), and ending in Stage 8,which is mature white spruce. In an overview of plant habitat associations of Douglas-fir forests of the Pacific Northwest, Ruggiero and others  report that fairy slipper was present in young Douglas-fir age classes (35-79 years), but was much more common in mature (80 to 195 years) and old-growth (200 to 730 years) age classes. Case  reports that fairy slipper usually grows in shade and does not occur on mineral soils, suggesting a preference for late succession.
Fairy slipper reproduces by seed and vegetative means .
Breeding system: Fairy slipper is monoecious and cannot self-pollinate .
Pollination: Proctor and Harder  suggest that the natural unit of fairy slipper pollen deposition (the pollinium flake) contains sufficient pollen to fertilize most ovules. They also suggest that the pollen load affects the seed number. Pollination requires assistance of bumblebees .
Seed production: The seed production of fairy slipper is directly affected by the amount of pollen deposited on the stigma. Seed production is greater when there is more pollen deposited . An average seed count per capsule ranges between 10 and 20,000 .
Seed dispersal: No information is available on this topic.
Seed banking has not been documented in fairy slipper. Maryland field and greenhouse studies documented a seed bank in 7 other orchid genera, however. Soil-stored seed remained viable for 3 to 7 years of the 7-year study period at germination rates ranging from 30.5% to 74.9%. In greenhouse trials, orchids growing in soil inoculated with mycorrhizal fungi showed greatly increased germination rates compared to orchids in uninoculated soil . Although fairy slipper was not tested, these results suggest that fairy slipper may have a seed bank and require mycorrhizaal associates for best germination. Further research is needed on fairy slipper's life history.
Germination: Most fairy slippers require one of a number of different mycorrhizal fungi in the protocorm (1st stage of seed germination) tissue for germination to take place . Arditti and others  report that in the greenhouse, seeds from ripe capsules germinated very poorly or not at all, while 80% of immature seed in green capsules germinated. This suggests that fairy slipper seeds become less viable over time.
Seedling establishment/growth: Seedlings are rare in the Great Lakes region, but are "much more common" in mountainous regions of the West .
Asexual regeneration: Fairy slipper sprouts from underground corms. Following anthesis the nodal region of the corm gives rise to a new shoot bud, which will become the new corm. The previous year's corms remain in sequence, attached to the younger corms for 2 to 4 years .
Growth Form (according to Raunkiær Life-form classification)
Broad-scale Impacts of Plant Response to Fire
in the Selway-Bitterroot Wilderness, Moose Creek Ranger District, Nez Perce NF"  notes
that after the 1977 Pattee Canyon Fire in Missoula, Montana, fairy slipper survived only the
"lightest" burning treatment. Even then, there was probably a reduction in the
fairy slipper population .
Life History and Behavior
More info for the term: corm
Following anthesis, the current year's corm gives rise to one shoot bud that forms a pair of root primordia. The root buds elongate as the shoot elongates and expands to form the new corm. The parent corm persists, and its leaf withers. By the end of the growing season, the new shoot has formed, and a leaf arises from its apex and overwinters [16,17,38,59].
The following table shows anthesis periods for fairy slipper:
|Maine and Vermont||May and June |
|Michigan||late May-early June; fruit ripens from June-July |
|New Mexico||June-August |
|Great Plains||late May-June |
|Intermountain west||May-July |
|Pacific northwest||March-June |
|Rocky Mountains||late May-June |
|Willamette, Mt. Hood, and Siuslaw National Forests, Oregon||March-June |
|New England and adjacent Canada||May and June |
|Great Lakes||early May-early June |
Molecular Biology and Genetics
Barcode data: Calypso bulbosa
Statistics of barcoding coverage: Calypso bulbosa
Public Records: 3
Specimens with Barcodes: 5
Species With Barcodes: 1
National NatureServe Conservation Status
Rounded National Status Rank: N5 - Secure
Rounded National Status Rank: NNR - Unranked
NatureServe Conservation Status
Rounded Global Status Rank: G5 - Secure
Reasons: Plant widely distributed but local. Listed as nationally rare in USA by Crow (1982). Range is circumboreal; Labrador to Alaska, south to Maine, Michigan, New York, west into the Rockies, Arizona and California, also in Europe. Most often found in cool, mature cedar swamps or on slopes of mixed coniferous growth underlain by some type of calcareous bedrock. May be vulnerable to local reduction due to herbivory from overly abundant deer.
Fairy slipper is ranked as follows:
In general, harvesting of timber and therefore loss of habitat is the worst threat. Collecting is a threat wherever populations are known and accessible. Another potential factor is loss of canopy due to insect infestations and/or disease. Frost damage to the tubers may occur during some winters. Also, as noted by Judziewicz (2001), the species is vulnerable to reduction from herbivory by locally overabundant deer.
Vickery and Rooney feel that we do not have sufficient information about the sites in Maine to answer this question.
Preserve Selection and Design Considerations:
Enough buffer zone to ensure the protecton of the canopy must be provided.
Vickery and Rooney (August, 1983) initiated demographic studies on all the large and reasonably stable CALYPSO sites in Maine (Lee, Scraggly and Webster Lakes and Crystal Bog Preserve).
Rooney and McKellar have monitored the population at Crystal Preserve since 1979.
Biological Research Needs:
1. How long does CALYPSO BULBOSA live?
2. What triggers dormancy/flowering?
3. How specifically is this element adapted to limited competition and pH of the substrate?
4. What period of time is required from germinating seed to flowering plant?
5. Rate of vegetative spread by rhizomatous roots?
Fairy slipper is highly susceptible to even slight disturbances in its
environment . Trampling and picking are the primary reasons for its rapid decline
in some locations . Picking the flower
inevitably kills the plant, because the delicate roots break at even the
lightest pull on the stem [45,59]. A decline in the frequency of
fairy slipper, due largely to a growing illegal international trade, caused the
International Union for the Conservation of Nature and Natural Resources to list
fairy slipper as a species vulnerable to extinction on a global scale .
Transplanting or cultivating fairy slipper is rarely successful because of fairy
slipper's need for specific soil fungi that are not usually present on
transplant sites or in controlled
environments [17,45]. Although the fairy slipper is widespread in its
distribution, population extermination is conceivable if plants are not
considered within a management plan.
Relevance to Humans and Ecosystems
Other uses and values
Importance to Livestock and Wildlife
Information on fairy slipper's value to animals, including use as food and as cover to arthropods, is lacking (as of 2006).
CALYPSO BULBOSA lives in vegetationally mature THUJA swamps in the East and in mountainous regions in the West. Most disturbances would be man-caused (trampling, logging). Population fluctuations in the absence of human activities are probably caused by periodic openings in the canopy allowing light to penetrate to the forest floor and thus increasing competition and substrate temperature.
- Norna redirects here. For the Norse goddesses, see Norns.
Calypso is a genus of orchids containing one species, Calypso bulbosa, known as the calypso orchid, fairy slipper or Venus's slipper. It is a perennial member of the orchid family found in undisturbed northern and montane forests. It has a small pink, purple, pinkish-purple, or red flower accented with a white lip, darker purple spottings, and yellow beard. The genus Calypso takes its name from the Greek signifying concealment, as they tend to favor sheltered areas on conifer forest floors. The specific epithet, bulbosa, refers to the bulb-like corms.
Calypso orchids are typically 10 to 14 cm in height. Their little purple blooms can be a pleasant sporadic sight on hiking trails from late March onwards, though in the more northerly parts of their range they do not bloom until May and June. The plants live no more than five years.
This species' range is circumpolar, and includes California, the Rocky Mountain states and most of the most northerly states of the United States; most of Canada; Scandinavia much of European and Asiatic Russia; China, Mongolia, Korea and Japan—see external links for map.
Although the calypso orchid's distribution is wide, it is very susceptible to disturbance, and is therefore classified as threatened or endangered in several U. S. states and in Sweden and Finland. It does not transplant well owing to its mycorrhizal dependence on specific soil fungi. The corms have been used as a food source by North American native peoples. The Thompson River Indians of British Columbia used it as a treatment for mild epilepsy.
At least near Banff, Alberta, the calypso orchid is pollinated by bumble bees (Bombus (Pyrobombus) and Psithyrus). It relies on "pollination by deception", as it attracts insects to anther-like yellow hairs at the entrance to the pouch and forked nectary-like structures at the end of the pouch but produces no nectar that would nourish them. Insects quickly learn not to revisit it. Avoiding such recognition may account for some of the small variation in the flower's appearance.
Four natural varieties and one nothovariety (variety of hybrid origin but established in the wild) are recognized:
- Calypso bulbosa var. americana (R.Br.) Luer - most of Canada, western and northern United States
- Calypso bulbosa var. bulbosa - Sweden, Finland, Baltic States, much of Russia, Mongolia, Korea
- Calypso bulbosa nothovar. kostiukiae Catling - Alberta (C. bulbosa var. americana × C. bulbosa var. occidentalis)
- Calypso bulbosa var. occidentalis (Holz.) Cockerell - from Alaska and British Columbia south through the Cacades, Rockies, and Sierra Nevada to California
- Calypso bulbosa var. speciosa (Schltr.) Makino - Japan, China (Gansu, Jilin, Nei Mongol, Sichuan, Tibet, Yunnan)
- Kew World Checklist of Selected Plant Families
- Coleman, Ronald A. (2002), The Wild Orchids of Arizona and New Mexico, Nature, pp. 21–26, ISBN 0-8014-3950-7, retrieved 2009-06-27
- C.Michael Hogan, ed. 2010. Calypso bulbosa. Encyclopedia of Life.
- Boyden, Thomas C. (1982), "The pollination biology of Calypso bulbosa var. Americana (Orchidaceae): Initial deception of bumblebee visitors", Oecologia 55 (2): 178–184, doi:10.1007/bf00384485, retrieved 2009-06-27
- Moerman, Daniel E. (1998), Native American ethnobotany, Timber Press, p. 133, ISBN 0-88192-453-9
- Mosquin, T. (1970), "The Reproductive Biology of Calypso bulbosa (Orchidaceae)", Can. Field-Nat. (84): 291–296 Summarized by Coleman and by Boyden
- Flora of China v 25 p 252, 布袋兰 bu dai lan, Calypso bulbosa var. speciosa
Names and Taxonomy
Comments: Distinct species; var. americana is very similar to var. occidentalis.
American varieties are [26,42]:
Calypso bulbosa var. americana (R. Br. ex Ait. f.) Luer
Calypso bulbosa var. occidentalis (Holz.) Boivin
EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.
To request an improvement, please leave a comment on the page. Thank you!