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AUTHORSHIP AND CITATION:
Reeves, Sonja L. 2005. Calypso bulbosa.
In: Fire Effects Information System, [Online].
U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station,
Fire Sciences Laboratory (Producer). Available:
https://www.fs.usda.gov/database/feis/plants/forb/calbul/all.html [].
FEIS ABBREVIATION:
CALBUL
SYNONYMS:
Cytherea bulbosa (L.) House [42]
NRCS PLANT CODE [71]:
CABU
CABUA
CABUO
COMMON NAMES:
fairy slipper
Venus' slipper
Calypso orchid
angel slipper
TAXONOMY:
The scientific name of fairy slipper is Calypso bulbosa (L.) Oakes (Orchidaceae)
[20,21,26,30,39,42,43,47,73]. Calypso is a monotypic genus [31]. Accepted North
American varieties are [26,42]:
Calypso bulbosa var. americana (R. Br. ex Ait. f.) Luer
Calypso bulbosa var. occidentalis (Holz.) Boivin
LIFE FORM:
Forb
FEDERAL LEGAL STATUS:
None
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 |
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].
ECOSYSTEMS [29]:AK | AZ | CA | CO | ID | ME | MI | MN | MT | NM | OR | SD | UT | VT | WA | WI | WY |
AB | BC | MB | NB | NF | NT | NS | NU | ON | PE | PQ |
SK | YK |
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
SRM (RANGELAND) COVER TYPES [66]:
409 Tall forb
411 Aspen woodland
ALASKAN RANGELANDS
920 White spruce-paper birch
HABITAT TYPES AND PLANT COMMUNITIES:
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].
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].
RAUNKIAER [61] LIFE FORM: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].
SITE CHARACTERISTICS:
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] |
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] |
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. Find further fire regime information for the plant communities in which this species may occur by entering the species name in the FEIS home page under "Find Fire Regimes".
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] |
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