Print Report
CEGL001976 Paronychia pulvinata - Silene acaulis Alpine Fell-field
Type Concept Sentence: No Data Available
Common (Translated Scientific) Name: Rocky Mountain Nailwort - Moss Campion Alpine Fell-field
Colloquial Name: No Data Available
Hierarchy Level: Association
Type Concept: This alpine association occurs on windswept alpine ridges and fell-fields throughout the southern Rocky Mountains. Most stands occur well above treeline. Slopes range from level to moderate (1-25%), and generally are on windward slopes (north- to west-facing aspects in the Southern Rockies). Total vegetation cover (vascular and nonvascular) rarely exceeds 40% and in some sites is closer to 25%, whereas rock, gravel and bare ground may cover 60% or more of a site. The vegetation occurs in mats, with few species growing on bare areas between the mats. Characteristic dominants include Paronychia pulvinata, Minuartia obtusiloba, Trifolium nanum, and Silene acaulis. Lichens and mosses have relatively high diversity and cover in this association. Stands of this association may cover large areas on windswept ridgetops, but less harsh microhabitats within the community will support small inclusions of alpine turf associations.
Diagnostic Characteristics: No Data Available
Rationale for Nominal Species or Physiognomic Features: No Data Available
Classification Comments: The Paronychia pulvinata coverage does not always overwhelmingly dominate the ground cover. In fact, it may not be more abundant than some forbs. However, in relatively large enough concentrations it is diagnostic of this association. The general community type is well-described, although the exact dominant species may vary from site to site.
Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: No Data Available
Floristics: This cushion plant association is characteristic of alpine fell-fields in the high peaks of the southern Rocky Mountains. Lichens and mosses have relatively high diversity and cover in this association (Willard 1963). Total vegetation cover (vascular and nonvascular) rarely exceeds 40% and in some sites is closer to 25%. The vegetation occurs in mats, with few species growing on bare areas between mats. Characteristic dominants include Paronychia pulvinata, Minuartia obtusiloba (= Arenaria obtusiloba), Trifolium nanum, and Silene acaulis. Stands may cover large areas on windswept ridgetops, but less harsh microhabitats within the community will support small inclusions of alpine turf associations.
Dynamics: The cushion plants that comprise this fellfield association are adapted to thriving in alternating cycles of short wet periods and long dry periods. Sites tend to be blown free of snow for most of the winter but may be covered by heavy wet snows in the spring. Following spring snowmelt, there is little moisture available to these communities other than summer thunderstorms (Willard 1963).
A number of authors (Willard 1963, Eddleman 1967, Welden 1985) discuss the role of succession in alpine cushion plant communities; namely that they represent an early-seral stage of plants that can become established in harsh, dry, windswept sites with little soil. As soils and sheltered microsites for germination develop, the cushion plants will be replaced by taller species such as Geum rossii. However, because the sites remain snow-free for much of the winter and are continually windswept, it is unlikely that cushion plant communities would ever convert completely to taller, more mesic alpine meadows.
A number of authors (Willard 1963, Eddleman 1967, Welden 1985) discuss the role of succession in alpine cushion plant communities; namely that they represent an early-seral stage of plants that can become established in harsh, dry, windswept sites with little soil. As soils and sheltered microsites for germination develop, the cushion plants will be replaced by taller species such as Geum rossii. However, because the sites remain snow-free for much of the winter and are continually windswept, it is unlikely that cushion plant communities would ever convert completely to taller, more mesic alpine meadows.
Environmental Description: This alpine association occurs on windswept alpine ridges and fellfields in the southern Rocky Mountains of Colorado, New Mexico, Arizona, Utah and Wyoming. Most stands tend to occur well above treeline, but on Wheeler Peak in northern New Mexico, this community extends from treeline to the tops of the highest ridges (Baker 1983a). Slopes range from level to moderate (1-25%), and generally are on windward slopes (north- to west-facing aspects in the southern Rockies). Stands have the appearance of an "alpine desert" (Willard 1963) because the vegetation covers much less of the ground than do exposed rock, gravel and bare soil. Soils are very shallow, gravelly and extremely rocky. The underlying geology includes granitic and metamorphic rocks, as well as extrusive volcanic rocks.
Geographic Range: This association is known from dry alpine habitats in Colorado, northern New Mexico, northeastern Utah and southern Wyoming.
Nations: US
States/Provinces: AZ, CO, NM?, UT, WY
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.686365
Confidence Level: Low
Confidence Level Comments: No Data Available
Grank: G5
Greasons: No Data Available
| Type | Name | Database Code | Classification Code |
|---|---|---|---|
| Class | 4 Polar & High Montane Scrub, Grassland & Barrens Class | C04 | 4 |
| Subclass | 4.B Temperate to Polar Alpine & Tundra Vegetation Subclass | S12 | 4.B |
| Formation | 4.B.1 Temperate & Boreal Alpine Tundra Formation | F037 | 4.B.1 |
| Division | 4.B.1.Nb Western North American Alpine Tundra Division | D043 | 4.B.1.Nb |
| Macrogroup | 4.B.1.Nb.2 Eight-petal Mountain-avens - Blackroot Sedge - Moss Campion Alpine Tundra Macrogroup | M099 | 4.B.1.Nb.2 |
| Group | 4.B.1.Nb.2.b Blackroot Sedge - Bellardi Bog Sedge - Cushion Phlox Alpine Turf & Fell-field Group | G314 | 4.B.1.Nb.2.b |
| Alliance | A3154 Twin-flower Sandwort - Rocky Mountain Nailwort - Moss Campion Alpine Fell-field Alliance | A3154 | 4.B.1.Nb.2.b |
| Association | CEGL001976 Rocky Mountain Nailwort - Moss Campion Alpine Fell-field | CEGL001976 | 4.B.1.Nb.2.b |
Concept Lineage: No Data Available
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: = Paronychia - Silene - Chalicodium Alpine Mat Formation (Clements 1904)
= Paronychia pulvinata / Lidia biflora Plant Association (Johnston 1987)
= Paronychia - Cushion Community (Eddleman 1967)
= Sileneto-Paronychietum Association (Willard 1963)
= Association Silene-Paronychietum (Willard 1963) (Komarkova 1979)
= Cushion Community (Baker 1983a)
= Cushion Plant Community (Lewis 1970)
= Cushion Stand (Welden 1981)
= Paronychia pulvinata / Lidia biflora Plant Association (Johnston 1987)
= Paronychia - Cushion Community (Eddleman 1967)
= Sileneto-Paronychietum Association (Willard 1963)
= Association Silene-Paronychietum (Willard 1963) (Komarkova 1979)
= Cushion Community (Baker 1983a)
= Cushion Plant Community (Lewis 1970)
= Cushion Stand (Welden 1981)
- Baker, W. L. 1980a. Alpine vegetation of the Sangre De Cristo Mountains, New Mexico: Gradient analysis and classification. Unpublished thesis, University of North Carolina, Chapel Hill. 55 pp.
- Baker, W. L. 1983a. Alpine vegetation of Wheeler Peak, New Mexico, USA: Gradient analysis, classification, and biogeography. Arctic and Alpine Research 15(2):223-240.
- Bell, K. L., and L. C. Bliss. 1979. Autecology of Kobresia bellardii: Why winter snow accumulation limits local distribution. Ecological Monographs 49(4):377-402.
- Benedict, J. B. 1977b. A master plan for the Bunker Hill Placer Preserve, Boulder County, Colorado. Unpublished report prepared for The Nature Conservancy, Denver, CO. 61 pp.
- Bourgeron, P. S., and L. D. Engelking, editors. 1994. A preliminary vegetation classification of the western United States. Unpublished report. The Nature Conservancy, Western Heritage Task Force, Boulder, CO. 175 pp. plus appendix.
- Braun, C. E. 1969. Population dynamics, habitat, and movements of white-tailed ptarmigan in Colorado. Unpublished dissertation, Colorado State University, Fort Collins. 189 pp.
- CNHP [Colorado Natural Heritage Program]. 2006-2017. Tracked natural plant communities. Colorado Natural Heritage Program, Colorado State University, Fort Collins. [https://cnhp.colostate.edu/ourdata/trackinglist/plant_communities/]
- Clements, F. E. 1904. Formation and succession herbaria. University of Nebraska, University Studies IV(4):329-355.
- Clements, F. E., and G. W. Goldsmith. 1924. Climaxes and climates of the Pike''s Peak region. Pages 14-16 in: The phytometer method in ecology: The plant and community as instruments. Carnegie Institute of Washington Publication No. 356.
- Cox, C. F. 1933. Alpine plant succession on James Peak, Colorado. Ecological Monographs 3:299-372.
- Daubenmire, R. F. 1943. Vegetational zonation in the Rocky Mountains. Botanical Review 9:325-393.
- Dix, R. L. 1974. Regional ecological systems of Colorado. Pages 7-17 in: P. O. Foss, editor. Environment and Colorado: A handbook. Environmental Resources Center, Colorado State University, Fort Collins.
- Eddleman, L. E. 1967. A study of phyto-edaphic relationships in alpine tundra of northern Colorado. Unpublished dissertation, Colorado State University, Fort Collins. 148 pp.
- Greller, A. M. 1974. Vegetation of roadcut slopes in the tundra of Rocky Mountain National Park, Colorado. Biological Conservation 6(2):84-93.
- Johnston, B. C. 1987. Plant associations of Region Two: Potential plant communities of Wyoming, South Dakota, Nebraska, Colorado, and Kansas. R2-ECOL-87-2. USDA Forest Service, Rocky Mountain Region. Lakewood, CO. 429 pp.
- Knight, D. H., and J. F. Thilenius. 1975. Vegetation ecology. Pages 37-59, 99-104 in: D. H. Knight, et al., editors. The Medicine Bow Ecology Project: The potential sensitivity of various ecosystem components to winter precipitation management in the Medicine Bow Mountains, Wyoming. Unpublished report prepared for the Office of Atmospheric Water Resources, USDI Bureau of Reclamation, by the University of Wyoming, Laramie.
- Komarkova, V. 1979. Alpine vegetation of the Indian Peaks area, Front Range, Colorado Rocky Mountains. Flora et vegetatio mundi 7, R. Tuxen, editor, 2 volumes, Vaduz: J. Cramer. 591 pp.
- Lewis, M. E. 1970. Alpine rangelands of the Uinta Mountains, Ashley and Wasatch national forests, Region 4 of the USDA Forest Service. Unpublished report mimeographed for USDA Forest Service, Region IV, Ogden, UT. 75 pp.
- Salas, D. E., J. Stevens, K. Schulz, M. Artmann, B. Friesen, S. Blauer, E. W. Schweiger, and A. Valdez. 2010b. Vegetation classification and mapping project report: Great Sand Dunes National Park and Preserve. Natural Resource Report NPS/ROMN/NRR--2010/179. National Park Service, Fort Collins, CO.
- Salas, D., J. Stevens, and K. Schulz. 2005. USGS-NPS Vegetation Mapping Program: Rocky Mountain National Park, Colorado. Technical Memorandum No. 8260-05-02. USDI Bureau of Reclamation, Denver, CO. 161 pp. plus Appendices A-L (733 pp.).
- Scott-Williams, B. W. 1965. The ecology of the alpine tundra on Trail Ridge. Pages 13-16 in: C. B. Schulz and H. T. Smith, editors. Guidebook for one-day field conferences -- Boulder area, Colorado. VIIth International Association for Quaternary Research Congress, Nebraska Academy of Science, Lincoln, NE.
- USFS [U.S. Forest Service]. 1983b. Plant associations of Region Two. Third edition. USDA Forest Service, Region Two, Range, Wildlife, and Ecology, Denver, CO. 379 pp.
- Welden, C. 1985. Structural pattern in alpine tundra vegetation. American Journal of Botany 72(1):120-134.
- Welden, C. W. 1981. Pattern in alpine tundra. Unpublished thesis, Colorado State University, Fort Collins. 144 pp.
- Western Ecology Working Group of NatureServe. No date. International Ecological Classification Standard: International Vegetation Classification. Terrestrial Vegetation. NatureServe, Boulder, CO.
- Willard, B. E. 1963. Phytosociology of the alpine tundra of Trail Ridge, Rocky Mountain National Park, Colorado. Unpublished dissertation, University of Colorado, Boulder.
- Willard, B. E. 1979. Plant sociology of alpine tundra, Trail Ridge, Rocky Mountain National Park, Colorado. Colorado School of Mines Quarterly 74(4):1-119.