Calypso bulbosa

In autumn, generally around September, the single, dark green leaf of the fairy slipper orchid sprouts from the corm (2) (4) (7). This leaf lasts through winter, even surviving under snow in the cold parts of its range (2) (4). With the arrival of spring, the orchid flowers. In Europe, this may be as soon as the snow melts (5), while in parts of North America it is said to occur in May and June (2) (7), and the flower is able to withstand any late frosts that may occur. Shortly after the flower blooms, the leaf fades for the summer (4). The flower of the fairy slipper orchid possesses no nectar and instead attracts its pollinators by deception (5). The scent and shape of the flower mimics those that do have nectar, which lures bumble bees (Bombus species) to the bloom (5). The bees land on the lip of the flower and enter the pouch in search of food. Failing to find any, the bee exits the pouch, rubbing against the column overhanging the pouch opening as it does so. Pollen is deposited on the bee and is then transferred to the next flower it visits (4). Following pollination, the fairy slipper orchid flower fades rapidly (2). By late summer, the capsule has ripened and the seeds are dispersed. The leaf withers and the plant becomes dormant until September, when a new leaf will be produced and the cycle will commence again (7).

The fairy slipper orchid, which has been called the most beautiful terrestrial orchid in North America (4), bears a single, showy flower on a single, dainty, purple stem (4) (5) (6). The petals and sepals of each intricate and colourful flower are held above a large, highly-modified petal (called the lip) like a crown (2) (7). The lip is a slipper-shaped pouch, hence this plant's common name (2). The flowers, which emit a distinct, pleasant, vanilla-like aroma (4) (5), range in colour from rich purple, through shades of pink to white and are lightly veined (2) (4), while the lip is white to purple with purplish spots, and the inside of the pouch is lined with purple to reddish veins (2) (4). The area near the throat of the pouch is decorated with three ridges, bearing white or yellow hairs (2) (4). Each plant has a single, dark green, oval leaf measuring up to 3.5 centimetres long (2) (6). Both the single leaf and flower stem rise from a shallow corm, with few, short and slender roots (2) (4). On blooming plants it is sometimes possible to see the top of the corm (4). The species name bulbosa refers to the bulb-like nature of the corms (2), while Caplypso comes from the name of the sea nymph in Homer's Odyssey (5). Four varieties of the fairy slipper orchid are recognised, each differing slightly in their appearance (2).

The fairy slipper orchid has a circumpolar distribution, occurring in Europe, Asia and North America (5). In Europe is does not grow south of 57 ºN (5), and in North America is occurs from Alaska to Labrador, south to northern California, Arizona, Michigan and Maine (6). Calypso bulbosa var. bulbosa occurs in Europe and Asia, Calypso bulbosa var. speciosa is found in Japan, while Calypso bulbosa var. Americana and Calypso bulbosa var. occidentalis both occur in North America (2)

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

United States

Origin: Unknown/Undetermined

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

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 [42]. 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 [26].

(key to state/province abbreviations)
UNITED STATES AK AZ CA CO ID ME MI MN MT NM OR SD UT VT WA WI WY
CANADA AB BC MB NB NF NT NS NU ON PE PQ SK YK

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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 [11]:

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

Calypso bulbosa (L.) Oakes:
Canada (North America)
United States (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Global Range: Circumboreal species; Labrador to Alaska, south to Maine, Michigan, New York, west into the Rockies, Arizona and California, also in Europe.

More info for the terms: corm, forb

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 [17].

Plants 4.5–22 cm. Leaves: blade elliptic to suborbiculate or ovate, often cordate, 10–65 × 12–52 mm. Inflorescences: floral bracts lance-acuminate, 5–28 mm. Flowers pink, magenta, or rarely white; sepals and petals erect-spreading, linear-lanceolate to linear-oblong, 10–24 × 1.5–5 mm; lip 13–23 × 4–13 mm, lamina shorter than to longer than apical horns, basal bristles sparse to extensive, brightly and contrastingly colored to dull and obscure. Capsules erect, ellipsoid to lanceoloid, 2–3 × 1–1.5 cm. 2n = 28 [var. bulbosa].

Cypripedium bulbosum Linnaeus, Sp. Pl. 2: 951. 1753; Cytherea bulbosa (Linnaeus) House

More info for the terms: constancy, series

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 [53]

ID: Western larch-Douglas-fir (Larix occidentalis-Pseudotsuga menziesii) forests, Priest River Experimental Forest [48]

MT: Engelmann spruce/sweet-scented bedstraw (Picea engelmannii/Galium triflorum)
and

       subalpine fir/red baneberry (Abies lasiocarpa/Actaea rubra) habitat types [32]

WY: Jackson Hole Wildlife Park — Fir-spruce and
lodgepole pine (Pinus contorta) habitats [62]

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 [28]

       Olympic National Park: coniferous
forest plant associations [36]

OR: Cascade Range white fir (Abies concolor) series with
constancy values ranging
from 3%-50%

       western hemlock (Tsuga heterophylla)
Cascade Range series at 2% constancy [6]

       Siskiyou Mountain Province: Tanoak (Lithocarpus densiflorus)
associations [7]

       Willamette and Siuslaw National Forests: western hemlock series [34,35].

       Grand fir (Abies grandis) series

        Douglas-fir associations on the Willamette National Forest [35].

       Willamette Valley — Douglas-fir forests [27]

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
stellatum) [6,18].

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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 [66]:

409 Tall forb

411 Aspen woodland

ALASKAN RANGELANDS

920 White spruce-paper birch

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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 [23]:

5 Balsam fir

12 Black spruce

13 Black spruce-tamarack

16 Aspen

30 Red spruce-yellow birch

32 Red spruce

33 Red spruce-balsam fir

37 Northern white-cedar

38 Tamarack

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

232 Redwood

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

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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 [46] 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

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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):

ECOSYSTEMS [29]:

FRES10 White-red-jack pine

FRES11 Spruce-fir

FRES19 Aspen-birch

FRES20 Douglas-fir

FRES21 Ponderosa pine

FRES22 Western white pine

FRES23 Fir-spruce

FRES24 Hemlock-Sitka spruce

FRES25 Larch

FRES26 Lodgepole pine

FRES27 Redwood

FRES29 Sagebrush

Fairy slipper is found beneath moist soils rich with decaying leaves and wood [40,41,50,55]. . Populations in south-central Montana were recorded on north and north-east aspects where it is cool and moist [52]. It typically occurs in cool, shady areas, from sea level to mid-montane elevations [40,41,50,55], and tolerates boreal climates north of the Great Lakes region [13]. The following table provides elevations where fairy slipper has been collected.

State/Region/Province

Elevation Arizona 8,500 to 10,000 feet (2,590-3,048 m) [43] California <5,900 feet  (<1,800 m) [37] Colorado 7,000 to 10,000 feet (2,134-3,048 m) [33] New Mexico 7,000 to 10,000 feet (2,134-3,048 m) [51] Utah 8,900 to 10,500 feet (2,700-3,200 m) [74] 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) [52] Alberta 1,600 to 5,200 feet (500-1,600 m) [15]

Comments:

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.

The fairy slipper orchid occurs in forests and woodlands (6), generally in shady areas (4) (5), where it grows in humus (4) (7), or in the decaying vegetation covering the forest floor (2) (4). It may also grow in sphagnum bogs (5), moss, or on top of rotting logs and tree stumps (4).

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.

More info for the terms: fire management, fuel, prescribed fire

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.

More info for the terms: corm, ground fire, litter, top-kill

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 [14]. 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 [12]. 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.

Fairy slipper is probably top-killed by fire. Underground organs such as corms are usually protected from even severe overstory fires [14,44]. However, there are no data to date (2006) on burial depth of fairy slipper corms. Fire may damage shallowly buried corms.

More info for the term: geophyte

POSTFIRE REGENERATION STRATEGY [67]:
Geophyte, growing points deep in soil

More info for the terms: corm, fire regime, stand-replacement fire, succession, surface fire

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 [14]. Its ability to regenerate from seed after fire is undocumented. Case's [13] 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 [22] to short-return interval surface fire in ponderosa pine forests of the western United States [2]. 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 [2] tamarack Larix laricina 35-200 [58] 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 [22] Engelmann spruce-subalpine fir Picea engelmannii-Abies lasiocarpa 35 to >200 [2] black spruce Picea mariana 35-200 conifer bog* Picea mariana-Larix laricina 35-200 red spruce* Picea rubens 35-200 [22] 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 [2] 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 [2] 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 [2] *fire return interval varies widely; trends in variation are noted in the species review

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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 [44]. 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 [72]), 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 [64] 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 [13] reports that fairy slipper usually grows in shade and does not occur on mineral soils, suggesting a preference for late succession.

More info for the terms: capsule, corm, monoecious, natural

Fairy slipper reproduces by seed and vegetative means [55].

Breeding system: Fairy slipper is monoecious and cannot self-pollinate [55].

Pollination: Proctor and Harder [60] 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 [55].

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 [60]. An average seed count per capsule ranges between 10 and 20,000 [45].

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 [75]. 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 [17]. Arditti and others [1] 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 [13].

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 [17].

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More info for the term: geophyte

RAUNKIAER [61] LIFE FORM:
Geophyte

More info for the term: forb

Forb

A broad analysis of vegetative responses to fire compiled for "Fire Management
in the Selway-Bitterroot Wilderness, Moose Creek Ranger District, Nez Perce NF" [44] 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 [44].

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.

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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:

State/Region Flowers Arizona June-August [43] California March-July [56] Maine and Vermont May and June [65] Michigan late May-early June; fruit ripens from June-July [38] New Mexico June-August [51] Great Plains late May-June [31] Intermountain west May-July [16] Pacific northwest March-June [40] Rocky Mountains late May-June [45] Willamette, Mt. Hood, and Siuslaw National Forests, Oregon March-June [70] New England and adjacent Canada May and June [30] Great Lakes early May-early June [13]

The following is a representative barcode sequence, the centroid of all available sequences for this species.

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 3
Specimens with Barcodes: 5
Species With Barcodes: 1

Canada

Rounded National Status Rank: N5 - Secure

United States

Rounded National Status Rank: NNR - Unranked

OTHER STATUS:
Fairy slipper is ranked as follows:

State Protection status Arizona Salvage restricted Michigan Threatened New Hampshire Endangered New York Endangered Vermont Threatened Wisconsin Threatened

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.

The fairy slipper orchid is listed on Appendix II of CITES (3).

Comments:

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.

Habitat destruction is a threat for the fairy slipper orchid in California, where logging for the timber industry is the primary cause (4). Logging and development also threatens the fairy slipper orchid throughout other parts of its range (2). Another significant threat to this stunning plant is the presence of people, either accidentally causing damage when they come to view and photograph these beautiful flowers, or, more seriously, when collectors deliberately remove the plants from the wild for cultivation in gardens (2) (4). In addition, the shallow growth of the fairy slipper orchid makes it susceptible to predation by feral pigs. In some areas, pigs have been known to destroy entire colonies (4).

More info for the terms: frequency, natural

Fairy slipper is highly susceptible to even slight disturbances in its
environment [17]. Trampling and picking are the primary reasons for its rapid decline
in some locations [59]. 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 [17]. 
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.

Restoration Potential:

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.

Monitoring Programs:

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?

The fairy slipper orchid is listed on Appendix II of the Convention on International Trade in Endangered Species (CITES), which means that any international trade in this species should be carefully monitored (2). Hopefully this may lessen the threat of over-collection. In addition, this species is protected within many parks and reserves throughout its range (4) (8).

Stewardship Overview:

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.