Cypripedium reginae - Walt.
Showy Lady's-slipper
Other Common Names: showy lady's slipper
Taxonomic Status: Accepted
Related ITIS Name(s): Cypripedium reginae Walt. (TSN 43538)
French Common Names: cypripède royal
Unique Identifier: ELEMENT_GLOBAL.2.159904
Element Code: PMORC0Q0D0
Informal Taxonomy: Plants, Vascular - Flowering Plants - Orchid Family
Kingdom Phylum Class Order Family Genus
Plantae Anthophyta Monocotyledoneae Orchidales Orchidaceae Cypripedium
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Concept Reference
Concept Reference: Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Concept Reference Code: B94KAR01HQUS
Name Used in Concept Reference: Cypripedium reginae
Conservation Status

NatureServe Status

Global Status: G4G5
Global Status Last Reviewed: 12Jan2016
Global Status Last Changed: 12Jan2016
Ranking Methodology Used: Ranked by inspection
Rounded Global Status: G4 - Apparently Secure
Reasons: Cypripedium reginae has an extensive range throughout much of eastern North America, but is infrequent or only very locally abundant throughout this range. The species is found from Newfoundland, Nova Scotia, Quebec, Ontario, Manitoba, and eastern Saskatchewan south to Virginia, Tennessee, Arkansas, and North Dakota. It is impacted by hydrologic disturbance and water contamination, collecting, and many other threats (although occurrences exist on many protected areas).
Nation: United States
National Status: NNR
Nation: Canada
National Status: N4N5 (12Jan2016)

U.S. & Canada State/Province Status
United States Alabama (SNR), Arkansas (S1), Connecticut (S1), Illinois (S1), Indiana (S3), Iowa (S2), Kentucky (SX), Maine (S3), Maryland (SU), Massachusetts (S3), Michigan (SNR), Minnesota (SNR), Missouri (S2S3), New Hampshire (S1), New Jersey (S1), New York (S3), North Carolina (SNA), North Dakota (S2S3), Ohio (S2), Pennsylvania (S2), Tennessee (S1), Vermont (S3), Virginia (S1), West Virginia (S1), Wisconsin (S4)
Canada Manitoba (S4), New Brunswick (S3), Newfoundland Island (S2), Nova Scotia (S2), Ontario (S4), Prince Edward Island (S2), Quebec (S3), Saskatchewan (S1)

Other Statuses

NatureServe Global Conservation Status Factors

Range Extent Comments: Cypripedium reginae has an extensive range throughout much of eastern North America. The species is found from Newfoundland, Nova Scotia, Quebec, Ontario, Manitoba, and eastern Saskatchewan south to Virginia, Tennessee, Arkansas, and North Dakota.

Number of Occurrences: 81 to >300
Number of Occurrences Comments: Numerous documented or published occurrences: Manitoba (over thirty-five), Ontario (approximately one hundred), Quebec (approximately twenty), Saskatchewan (one); Arkansas (two), Connecticut, Iowa (eight counties), Illinois (five), Indiana (over twenty), Massachusetts, Maine (twenty-one), Michigan (sixty-one counties), Minnesota (thirty-three counties), Missouri (twenty-seven), New Hampshire (six), New Jersey (one), New York (thirty counties), North Dakota (approximately twenty-one), Ohio (seven), Pennsylvania (nine), Tennessee (two), Vermont (fifty-nine), Virginia (two-four), Wisconsin (forty-three), West Virginia (two). [Of the ranked occurrences there are sixteen A-ranked occurrences, 2AB, 10B, 14C, and 19D assigned by individual states. However, following current RANKSPECS this would change to 6A, 12B, 24C, 19D. (These do not include un-documented populations, of which there are many and some of which are anecdotally A-ranked.)]

Population Size Comments: The species is widely distributed with numerous large populations (>1000) individuals still extant in portions of its range. Most populations have 10-100 plants.

Overall Threat Impact Comments: Primary threats include hydrologic disturbance (drainage of wetland areas; contamination of water sources, e.g. road salt run-off, infiltration of groundwater by brines brought up from drilling operations) and habitat disruption (logging impact, peat mining, soil compaction, canopy closure). Also threatened by loss of habitat, herbivory, and wildflower picking. Horticulturally traded, though advertised by several distributors as available laboratory-propagated. As noted by Judziewicz (2001), may be particularly vulnerable to local reduction due to herbivory from overly abundant deer.

Short-term Trend: Relatively Stable (<=10% change)
Short-term Trend Comments: Cypripedium reginae is still abundant over large portions of its range, particularly in the north, but is rare or is becoming rare on the periphery of its range. This is particularly true in the southern and eastern portions of its range. This species is still declining or disappearing in many areas due to various threats, especially collection by humans and loss of habitat to development.

Intrinsic Vulnerability Comments: The species is sensitive to canopy closure and alteration of water supply.

Other NatureServe Conservation Status Information

Global Range: Cypripedium reginae has an extensive range throughout much of eastern North America. The species is found from Newfoundland, Nova Scotia, Quebec, Ontario, Manitoba, and eastern Saskatchewan south to Virginia, Tennessee, Arkansas, and North Dakota.

U.S. States and Canadian Provinces
Color legend for Distribution Map

U.S. & Canada State/Province Distribution
United States AL, AR, CT, IA, IL, IN, KYextirpated, MA, MD, ME, MI, MN, MO, NCexotic, ND, NH, NJ, NY, OH, PA, TN, VA, VT, WI, WV
Canada MB, NB, NF, NS, ON, PE, QC, SK

Range Map
No map available.

U.S. Distribution by County Help
State County Name (FIPS Code)
AR Stone (05137)
CT Litchfield (09005), Tolland (09013)*
IA Allamakee (19005), Boone (19015)*, Bremer (19017), Chickasaw (19037), Clayton (19043), Delaware (19055), Dickinson (19059)*, Emmet (19063)*, Fayette (19065), Guthrie (19077)*, Hamilton (19079), Hancock (19081)*, Iowa (19095)*, Jackson (19097), Jasper (19099)*, Johnson (19103)*, Jones (19105)*, Linn (19113)*, Muscatine (19139)*, Poweshiek (19157)*, Story (19169)*, Tama (19171)*, Webster (19187)*, Winnebagao (19189)*, Winneshiek (19191)
IL Kendall (17093)*, Lake (17097), Mchenry (17111), Woodford (17203)*
MA Berkshire (25003), Essex (25009)*, Franklin (25011), Hampden (25013)*, Hampshire (25015)*, Middlesex (25017)*, Worcester (25027)*
ME Androscoggin (23001)*, Aroostook (23003), Cumberland (23005)*, Franklin (23007)*, Hancock (23009)*, Kennebec (23011), Knox (23013)*, Oxford (23017)*, Penobscot (23019), Piscataquis (23021), Sagadahoc (23023)*, Somerset (23025), Waldo (23027)*, Washington (23029)
MO Adair (29001)*, Carter (29035), Dallas (29059), Dent (29065)*, Douglas (29067), Franklin (29071)*, Howell (29091), Jefferson (29099)*, Mercer (29129)*, Oregon (29149), Ozark (29153), Putnam (29171)*, Reynolds (29179)*, Schuyler (29197)*, Shannon (29203), St. Charles (29183)*, St. Louis (29189)*, St. Louis (city) (29510)*, Sullivan (29211)*, Texas (29215)
ND Benson (38005)*, Cavalier (38019), Eddy (38027), Pembina (38067), Ramsey (38071)*, Ransom (38073), Richland (38077)
NH Coos (33007), Grafton (33009)
NJ Bergen (34003)*, Essex (34013)*, Hudson (34017)*, Morris (34027)*, Passaic (34031)*, Sussex (34037)*, Warren (34041)
OH Champaign (39021), Cuyahoga (39035)*, Geauga (39055), Pickaway (39129), Portage (39133), Summit (39153)*
PA Blair (42013)*, Butler (42019)*, Centre (42027)*, Clearfield (42033)*, Crawford (42039), Cumberland (42041), Erie (42049), Greene (42059)*, Huntingdon (42061)*, Juniata (42067)*, Lawrence (42073), Mercer (42085)*, Northampton (42095)*, York (42133)*
TN Claiborne (47025), Johnson (47091)
VA Giles (51071), Rockingham (51165)*, Shenandoah (51171), Washington (51191)
VT Addison (50001), Bennington (50003), Caledonia (50005), Orange (50017), Orleans (50019), Rutland (50021), Washington (50023), Windsor (50027)
WV Greenbrier (54025), Tucker (54093)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
01 Upper St. John (01010001)+, Allagash (01010002)+*, Fish (01010003)+, Aroostook (01010004)+, Meduxnekeag (01010005)+, Mattawamkeag (01020003)+, Piscataquis (01020004)+, Lower Penobscot (01020005)+, Upper Kennebec (01030001)+, Lower Kennebec (01030003)+, Lower Androscoggin (01040002)+*, St. Croix (01050001)+, Maine Coastal (01050002)+, St. George-Sheepscot (01050003)+*, Presumpscot (01060001)+*, Merrimack (01070002)+*, Upper Connecticut (01080101)+, Passumpsic (01080102)+, Waits (01080103)+, Upper Connecticut-Mascoma (01080104)+, White (01080105)+, Black-Ottauquechee (01080106)+, Middle Connecticut (01080201)+*, Deerfield (01080203)+, Westfield (01080206)+*, Farmington (01080207)+*, Charles (01090001)+*, Shetucket (01100002)+*, Housatonic (01100005)+
02 Hudson-Hoosic (02020003)+, Rondout (02020007)+*, Hackensack-Passaic (02030103)+*, Raritan (02030105)+*, Middle Delaware-Mongaup-Brodhead (02040104)+*, Middle Delaware-Musconetcong (02040105)+, Upper West Branch Susquehanna (02050201)+*, Bald Eagle (02050204)+*, Upper Juniata (02050302)+*, Raystown (02050303)+*, Lower Juniata (02050304)+*, Lower Susquehanna-Swatara (02050305)+, South Fork Shenandoah (02070005)+*, North Fork Shenandoah (02070006)+
04 Cuyahoga (04110002)+, Ashtabula-Chagrin (04110003)+, Mettawee River (04150401)+, Otter Creek (04150402)+, Winooski River (04150403)+, Lake Champlain (04150408)+, St. Francois River (04150500)+
05 French (05010004)+, Cheat (05020004)+, Shenango (05030102)+, Connoquenessing (05030105)+, Middle New (05050002)+, Greenbrier (05050003)+, Upper Scioto (05060001)+, Upper Great Miami (05080001)+
06 North Fork Holston (06010101)+, Watauga (06010103)+, Powell (06010206)+
07 Coon-Yellow (07060001)+, Upper Iowa (07060002)+, Grant-Little Maquoketa (07060003)+, Turkey (07060004)+, Maquoketa (07060006)+, Lower Wisconsin (07070005)+*, Copperas-Duck (07080101)+*, Upper Wapsipinicon (07080102)+, South Skunk (07080105)+*, North Skunk (07080106)+*, Winnebago (07080203)+*, Lower Cedar (07080206)+*, Upper Iowa (07080207)+*, Middle Iowa (07080208)+*, Lower Iowa (07080209)+*, Upper Des Moines (07100002)+*, East Fork Des Moines (07100003)+*, Middle Des Moines (07100004)+*, Boone (07100005)+, South Raccoon (07100007)+*, Peruque-Piasa (07110009)+*, Upper Fox (07120006)+, Lower Fox (07120007)+*, Lower Illinois-Senachwine Lake (07130001)+*, Cahokia-Joachim (07140101)+*, Meramec (07140102)+*
09 Devils Lake (09020201)+*, Upper Sheyenne (09020202)+*, Middle Sheyenne (09020203)+, Lower Sheyenne (09020204)+, Lower Red (09020311)+*, Lower Pembina River (09020316)+
10 Little Sioux (10230003)+*, Lower Grand (10280103)+*, Upper Chariton (10280201)+*, Lower Chariton (10280202)+*, Niangua (10290110)+, Lower Missouri (10300200)+*
11 Middle White (11010004)+, North Fork White (11010006)+, Upper Black (11010007)+*, Current (11010008)+, Eleven Point (11010011)+
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
Basic Description: North America's largest northern orchid. Herbaceous perennial to 1m; strong, fibrous root system; large leaves; flower showy, white- to rose-colored, petals and sepals broadly ovate and obtuse.
Habitat Comments: The habitat of Cypripedium reginae consists of cold northern wetlands (e.g., mossy conifer swamps of Thuja occidentalis, Picea mariana, or Larix laricina), swampy thickets, bogs, woodland glades, ravines, stream and lake edges, seepages on limestone or sandstone bluffs, damp calcareous slopes or shores, limestone quarries, wet calcareous meadows, circumneutral seep springs, forested fens, shrub borders of fens, sandy shorelines, and algific talus slopes. (Almendinger 1993, MO NHI 1993, W.R. Smith 1993, WPC 1993b, Homoya 1992, Labrecque 1992, NH NHI 1992, OH NHP 1992, VT NHP 1992, Gleason and Cronquist 1991, Roosa et al. 1989, Nekola 1987, Fernald 1970, Rickett 1963, Steyermark 1963, Gleason 1952, Deam 1940). Cypripedium reginae grows in soils ranging from slightly acidic to slightly alkaline. It has been observed growing in sphagnum as long as its roots are able to penetrate into deeper substrate layers that have a higher pH. It also prefers constant moisture and full sun to semi-shaded conditions associated plant species vary considerably between habitat type and across the range of the species.
Economic Attributes
Economically Important Genus: Y
Management Summary
Stewardship Overview: Cypripedium reginae ranges widely throughout eastern North America. There is extensive knowledge of habitat and associated species. Due to this knowledge, there is a strong understanding of the population trends and dynamics of this species. Most of the life history knowledge concerning C. reginae focuses on flowering, germination ecology and seedling development. There are numerous persistent threats to this species, including harvesting of the flowers and rootstocks for commercial and personal use, alteration of habitat through physical modification, alteration of hydrology, grazing pressure and encroachment by trees and shrubs. The major management requirement is maintenance of the hydrological integrity within occupied habitat and the prevention of over-collection. Monitoring programs are needed to track the status of existing populations with respect to on-going management practices. C. reginae is sensitive to prolonged dry conditions and excessive shade. Draw-down of water tables may likely lead to failures in recruitment and encroachment of shrubs and trees. Deer and cattle need to be controlled where browsing, grazing, and trampling is a problem, perhaps by erecting an enclosure around the affected population.
Restoration Potential: The restoration potential of C. reginae is largely unknown, although research efforts have been underway to address the complicated and difficult germination requirements of the species. In proper habitat and in the presence of appropriate myccorhizae fungi, long-term restoration may be likely. Seed germination, tissue culture, root division and transplantation may prove successful in restoration efforts. Cuttings do not survive well. Root division is a slow process, as plants typically produce only one or two plants per year. Laboratory culture is perhaps the only method that can produce fast results (Soucy 1979). Transplantation Successful growth and expansion of transplanted C. reginae individuals was obtained in an artificial bog constructed in garden settings. For a description and sketch of this structure, see Holman (1976). Olver (1981) had success growing transplanted individuals in controlled environmental conditions. See Olver (1981) for a description of her methods. Seed Collection, Germination and Growth Collection of seed while the pod is still green is necessary to reduce fungal and bacterial contamination of the seeds (Soucy 1979). Both immature and mature seeds germinate well (Linden 1980). Seeds require a darkness treatment in order to germinate. Cold stratification is apparently not required; immature seeds germinate well without a cold treatment, but mature seeds germinate better with one (Linden 1980). The temperate Cypripedium orchids possess impermeable seed coats that must be digested by bacteria or fungi prior to germination. In nature, this coat prevents premature germination and subsequent freezing. Seeds germinate poorly when sown in soil, but germinate well on Hyponex and also modified Curtis solution (Oliva and Arditti 1984). Formulation of the growth medium requires a precise mixture of all the major and minor nutrients required for optimum plant growth. Plant hormones also must be incorporated into the medium (Soucy 1979).
Preserve Selection & Design Considerations: The protection of wetland habitat and related ecological processes should be considered when designing preserves. Buffer areas should be incorporated to help maintain the integrity of orchid habitat. The size of preserves should be large enough to enable natural disturbance processes to occur (such as blowdown of trees in forest sites, that enable C. reginae to colonize suitable habitat). If habitats undergo succession or are not large enough to provide for expansion/colonization, management may be required to maintain openings.
Management Requirements: Education of the public is needed to curb picking and digging of plants (Lenz 1993b, Gawler 1992). In states where the species is protected by law, law enforcement agencies need to be made aware of the magnitude of this problem and devote more of their efforts toward controlling these activities. Deer and cattle need to be controlled where browsing, grazing, and trampling is a problem, perhaps by erecting an enclosure around the affected population. This would also deter human disturbance such as picking, poaching and trampling (Lenz 1993b, West Virginia Natural Heritage Program 1992). Maintenance of the hydrological integrity of occupied habitat is essential for the long-term existence of a population. Cypripedium reginae is sensitive to dry conditions and excessive shade, particularly if they are prolonged. Prolonged draw-down of water tables may likely lead to failures in recruitment and encroachment of shrubs and trees.
Monitoring Requirements: Depending on the rarity of the species within respective states/provinces, states may wish to implement monitoring programs to track the status of populations with respect to on- going management programs. Information pertaining to population size and status, number of individuals, reproductive success, habitat quality and threats should be gathered (Lenz 1993b, Ozark National Forest 1993, Cusick 1992, Gawler 1992).
Monitoring Programs: Amateur botanists are watching C. reginae sites in Missouri (Ladd 1993). Apparently, stem counts are being made on an annual basis. Contact: Doug Ladd, Director of Science, Stewardship and Registry, The Nature Conservancy, Missouri Field Office, 2800 S. Brentwood Blvd., St. Louis, MO 63144. Telephone: (314) 968-1105. The single occurrence in New Jersey is monitored by counting the number of stems and flowers present (Snyder 1993). Contact: David Snyder, Botanist, New Jersey Natural Heritage Program, Office of Natural Lands Management, 501 E. State St., CN404, Trenton, NJ 08625. Telephone: (609) 984-7849. Minimal monitoring of C. reginae populations is occurring in Pennsylvania through annual visits coupled with "eyeball" appraisals. Contact: Paul G. Wiegman, Director of Natural Science and Stewardship, Western Pennsylvania Conservancy, Natural Areas Program, 316 Fourth Ave., Pittsburgh, PA 15222. Telephone: (412) 288-2774.
Management Research Programs: Warren Stoutamire at the University of Akron (Ohio) works on the propagation of this species. Contact: Warren Stoutamire, University of Akron, Akron, OH. Telephone: (216) 375-7162. Mary DePauw is completing a M.S. thesis involving germination factors and tissue culture of several species of orchids, including C. reginae. Contact: Mary DePauw, Department of Plant Science, University of Manitoba, Winnipeg, Manitoba R3T 2N2. Telephone: (204) 479-8195.
Management Research Needs: Other management research needs include studying the effects of different management regimes on C. reginae, and developing management guidelines for the species. Examples include selective thinning, deer exclosures, rerouting human traffic around populations and hand pollination (Dobberpuhl 1992, Gawler 1992). There is a need to learn about the degree (if any) to which deer browsing limits populations (Dobberpuhl 1992, Gawler 1992). How long will an occurrence persist if the flowers are eaten each year?
Additional topics: The glandular hairs of the foliage contains a substance that can cause serious eczema or contact dermatitis, similar to that of poison ivy (WPC 1993b, Brackley 1985, Fernald 1970, Steyermark 1963, Correll 1950). Apparently the maximum effect of the irritant is reached during the formation of the capsule. Illustrations of C. reginae can be found in the following sources: W. R. Smith (1993), Vogt (1990), Summers (1987), Soucy (1979), Reyburn (1978: culture), Roedner et al. (1978), Teuscher (1977), Holman (1976), Luer (1975), Harvais (1973: culture, 1980), Peterson and McKenny (1968), Braun (1967), Gibson (1964), Stoutamire (1964: seeds and seedlings, 1967), Rickett (1963), Steyermark (1963), Gleason (1952), Correll (1950), Waterman (1949, 1950: plant and habitat) and Small (1933).
Population/Occurrence Delineation Not yet assessed
Population/Occurrence Viability
U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
NatureServe Conservation Status Factors Edition Date: 04Feb1994
NatureServe Conservation Status Factors Author: Ostlie, W.R. (1994); S.L. Neid (1998).
Management Information Edition Date: 09Feb1994
Management Information Acknowledgments: We are indebted to all the botanists, ecologists, information managers and others who took the time to provide the information necessary for the preparation of this and many other Element Stewardship Abstracts.

Botanical data developed by NatureServe and its network of natural heritage programs (see Local Programs), The North Carolina Botanical Garden, and other contributors and cooperators (see Sources).

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