Cypripedium Parviflorum (Yellow Lady’S Slipper Orchid)

1. Species: Cypripedium parviflorum (yellow lady’s slipper orchid)

2. Status: Table 1 summarizes the current status of this species or subspecies by various ranking entity and defines the meaning of the status.

Table 1. Current status of Cypripedium parviflorum Entity Status Status Definition NatureServe G5 Globally secure

CNHP G2 Imperiled in Colorado due to limited distribution and small population sizes Colorado None State List Status USDA Forest Sensitive Sensitive due to threats to individuals as well as habitat. Small scattered and Service isolated populations. The parent taxa Cypripedium parviflorum is sensitive in Region 2, which includes all of the subordinate taxa USDI FWSb None a Colorado Natural Heritage Program. b US Department of Interior Fish and Wildlife Service.

The 2012 U.S. Forest Service Planning Rule defines Species of Conservation Concern (SCC) as “a species, other than federally recognized threatened, endangered, proposed, or candidate species, that is known to occur in the plan area and for which the regional forester has determined that the best available scientific information indicates substantial concern about the species' capability to persist over the long-term in the plan area” (36 CFR 219.9). This overview was developed to summarize information relating to this species’ consideration to be listed as a SCC on the Rio Grande National Forest, and to aid in the development of plan components and monitoring objectives.

3. Taxonomy

This species and its varieties were previously known as Cypripedium calceolus ssp. parviflorum. The Flora of North America, ITIS, NatureServe, and the NRCS Plants National Database recognize Cypripedium parviflorum with 3 (var. makasin, var. parviflorum, and var. pubescens). Taxonomic work revealed that C. calceolus is an old world taxa while C. parviflorum is endemic to North America. The NRCS Plants Database lists both var. makasin and var. pubescens as being present in Colorado. Ackerfield (2015) lists only var. pubescens as being present in Colorado and Weber and Wittmann (2012) list only the parent taxa. This overview will just refer to the parent taxa since the element occurrences from the Colorado Natural Heritage Program uses the taxa C. calceolus var. parviflorum and it is unclear which of the new varieties that refers to.

4. Distribution, abundance, and population trend on the planning unit [12.53.2,3,4]: Yellow lady’s slipper orchid is not known from the Rio Grande NF, but its habitat certainly is. There are known occurrences on the San Juan NF less than 16 miles from the Rio Grande forest boundary. Of the 29 known occurrences in Colorado 16 are on NFS lands and 13 are on non-NFS lands. The occurrences on NFS lands are on the Pike-San Isabel NF (11), Arapaho-Roosevelt NF (2), and San Juan NF (3) and 6 of the NFS occurrences are more than 20 years old and are considered historic. Most occurrences of yellow lady’s slipper orchid are small (consisting of less than 100 individuals) and are spatially discrete (ranging from 5 or fewer individuals over a few square meters to 100 or more individuals scattered over 10 acres of meadow). Yellow lady’s slipper orchid tends to occur in isolated clumps that are distant from other occurrences. Trend is

unknown for many of the occurrences in Colorado, the few places with trend monitoring show generally stable populations, with noted impacts from recreation, grazing, and collecting. Additionally, population monitoring has indicated that populations fluctuate from year to year depending on precipitation and temperature.

Table 2. Known Occurrence Frequency within the Planning Area (Colorado Natural Heritage database) Known Occurrences in the past 20 years 0 Year Last Observed 0

5. Brief description of natural history and key ecological functions [basis for other 12.53 components]:

Yellow lady’s slipper orchid is a part of the forb community in the understory of aspen-mixed conifer forests from 5800-9800 feet in elevation in Colorado. It is also found near ephemeral seeps and springs and near fens and meadows. Unlike many rare plants yellow lady’s slipper orchid does not have exacting habitat requirements, rather it is a rare component of a common ecosystem. The distribution of this and most orchids is likely a driven by a combination of reproductive success (including the presence of pollinators and seed dispersal) and mycorrhizal fungal associations. It appears that yellow lady’s slipper orchid requires habitat that is outside of a climax community to survive likely as a function of needing some light but freedom from competitors (Mergen 2006).

6. Overview of ecological conditions for recovery, conservation, and viability [12.53 7, 9?, 10, 11, 12] including Threats and Risk Factors: Noted threats to yellow lady’s slipper orchid are managed and un-managed recreation, trampling and grazing from livestock, development, and collection of the showy flowers. As is noted in some of the Forest Service documentation for this species as a Sensitive species there are threats to this species from habitat alteration as well as individual plants being targeted by collectors. The aspen mixed conifer forest type associated with the yellow lady’s slipper orchid has been fairly intensively managed in the western US and some portions of that habitat are outside of their natural range of variation in terms of disturbance and forest structure. As a result, this species’ habitat has been altered in the past and is susceptible to being further altered by timber harvest, fire suppression, and ungulate damage. As is noted in Mergen (2006) this species seems to require habitat other than climax conditions to survive indicating that a departure from natural disturbance may be harmful to the species. Balancing restoration activities designed to bring these forests into line with the natural range of variation may damage existing individuals while creating habitat for the species across the landscape. The wetter components of this species’ habitat are susceptible to the alteration of hydrology, and the proliferation of invasive plants within and near yellow lady’s slipper habitat are consistently mentioned in the Element Occurrence reports from Colorado Natural Heritage Program.

7. Key literature:

Ackerfield, J. 2015. Flora of Colorado. Botanical Research Institute of Texas Press. Fort Worth, TX.

Colorado Natural Heritage Program (CNHP). 2015. Element Occurrence Records for Cypripedium calceolus ssp. parviflorum. Unpublished data stored on U.S. Forest Service Geographic Information Systems Servers. Compiled onto USFS Servers from CNHP database February 2015.

Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico. 19+ vols. New York and Oxford. Cypripedium parviflorum treatment accessed September 25, 2015 at http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id= 242101551

Integrated Taxonomic Information System (ITIS). 2015. Online database. http://www.itis.gov/ Accessed September 25, 2015.

Mergen, D.E. (2006). Cypripedium parviflorum Salisb. (lesser yellow lady’s slipper): a technical conservation assessment. US Forest Service, Rocky Mountain Region. Available: http://www.fs.fed.us/r2/projects/scp/assessments/cypripediumparviflorum.pdf

NatureServe, 2015. NatureServe Explorer. Online database. http://explorer.natureserve.org/index.htm Accessed September 25, 2015.

USDA NRCS Plants National Database. 2015. Online database. http://plants.usda.gov/ Accessed September 25, 2015.

Weber, W.A. and Wittmann, R.C. 2012. Colorado Flora 4th ed. University of Colorado Press. Boulder, CO.

8. Map of Known Occurrences and Modeled Suitable Habitat

Figure 1. Species Modeled Habitat and Reported Occurrences.