Print Report

CEGL001970 Geum rossii - Trifolium spp. Alpine Turf

Type Concept Sentence: No Data Available

Common (Translated Scientific) Name: Ross'' Avens - Clover species Alpine Turf

Colloquial Name: No Data Available

Hierarchy Level:  Association

Type Concept: This vegetation association has been described from the alpine zone of the Absaroka Mountains of northwestern Wyoming, the Beartooth Plateau of northwestern Wyoming, south-central Montana, and the Front Range of Colorado. Stands typically occur on sites where little snow accumulates but that are somewhat protected from the wind; they also occur on sites with moderate snow accumulation. Sites vary from gentle to steep lower to high slopes. Communities codominated by Trifolium parryi tend to be more wind-protected and accumulate more snow. Substrates are variable but tend to be shallow rocky, sandy loam soils, but sometimes are moderately deep, well-developed coarse-textured soils with high organic content. The vegetation is characterized by an open to dense herbaceous layer dominated by a combination of upright forbs and cushion plants with few graminoids. Geum rossii var. turbinatum dominates or codominates with a series of cushion plants (especially Trifolium nanum, Trifolium dasyphyllum, or Trifolium parryi, as well as Artemisia scopulorum, Arenaria congesta, Arenaria fendleri, Gentiana algida, Minuartia obtusiloba, Paronychia pulvinata, Phlox multiflora, Sedum lanceolatum, Silene acaulis, Smelowskia calycina, Tonestus pygmaeus); upright forbs (especially Erigeron simplex, Polygonum bistortoides, Polygonum viviparum, Cerastium arvense, Lomatium cous, Oxytropis parryi, Potentilla diversifolia, and Besseya wyomingensis) may contribute substantial cover. Calamagrostis purpurascens, Carex albonigra, Carex ebenea, Carex nardina, Carex heteroneura var. chalciolepis, Carex obtusata, Carex rupestris var. drummondiana, Deschampsia cespitosa, Festuca brachyphylla, Luzula spicata, Poa spp., and Trisetum spicatum are the most common graminoids. Some stands may contain low cover (5% cover or less) of dwarf-shrubs such as Artemisia arctica ssp. arctica, Salix reticulata, Salix brachycarpa, or Vaccinium scoparium.

Diagnostic Characteristics: No Data Available

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: This association is based on quantitative data and reasonably thorough descriptions from two alpine locations. In vegetation structure and habitat, it is similar to ~Geum rossii - Minuartia obtusiloba Alpine Fell-field (CEGL001965)$$, and this relationship should be reviewed carefully to determine whether the two associations should be merged. Some stands codominated by Trifolium parryi described by Thilenius and Smith (1985) occur in relatively mesic habitats (occurring in wind-protected areas with moderate snow accumulation) when compared to habitats of other Geum rossii - Trifolium spp. (Trifolium dasyphyllum and Trifolium nanum) communities. Further review is needed to resolve if grouping of all Trifolium spp. in this Geum rossii type is appropriate. There are many other similar Geum rossii-codominated associations that need further review and crosswalking to clarify classification.

Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: No Data Available

Floristics: This alpine plant association is characterized by an open to dense herbaceous layer dominated by a combination of upright forbs and cushion plants with few graminoids. Geum rossii var. turbinatum dominates or codominates with a series of cushion plants (especially Trifolium nanum, Trifolium dasyphyllum, or Trifolium parryi, as well as Artemisia scopulorum, Arenaria congesta, Arenaria fendleri, Gentiana algida, Minuartia obtusiloba, Paronychia pulvinata, Phlox multiflora, Sedum lanceolatum, Silene acaulis, Smelowskia calycina, Tonestus pygmaeus); upright forbs (especially Erigeron simplex, Polygonum bistortoides, Polygonum viviparum, Cerastium arvense, Lomatium cous, Oxytropis parryi, Potentilla diversifolia, and Besseya wyomingensis) may contribute substantial cover. Calamagrostis purpurascens, Carex albonigra, Carex ebenea, Carex nardina, Carex heteroneura var. chalciolepis, Carex obtusata, Carex rupestris var. drummondiana, Deschampsia cespitosa, Festuca brachyphylla, Luzula spicata, Poa spp., and Trisetum spicatum are the most common graminoids. Some stands may contain low cover (5% cover or less) of dwarf-shrubs such as Artemisia arctica ssp. arctica, Salix reticulata, Salix brachycarpa, or Vaccinium scoparium. A nonvascular stratum of mosses and lichen is typical and can cover up to 30%.

Dynamics:  Geum rossii has one of the widest ecological amplitudes among alpine taxa occurring in almost any alpine habitat (Komarkova 1986). However, there are few habitats where it can dominate, including disturbed areas (gopher gardens), and certain snowbed and fellfield communities (Willard 1963, Komarkova 1986).
Environmental Description:  This vegetation association has been described from the alpine zone of the Absaroka Mountains of northwestern Wyoming, the Beartooth Plateau of northwestern Wyoming, south-central Montana, and the Front Range of Colorado. Elevations range from 3450 to 3800 m (11,300-12,400 feet) in Colorado and above 3140 to 3355 m (10,300-11,000 feet) in Wyoming and Montana. Stands typically occur on sites where little snow accumulates, but that are somewhat protected from the wind; they also occur on sites with moderate snow accumulation. Sites vary from gentle to steep lower to high slopes. Communities codominated by Trifolium parryi tend to be more wind-protected and accumulate more snow (Thilenius and Smith 1985). Substrates are variable but tend to be shallow rocky, sandy loam soils, but sometimes are moderately deep, well-developed coarse-textured soils with high organic content. Soils are classified as Cryochrepts, Cryorthents, Cryoborolls, or Cryumbrepts (Thilenius and Smith 1985).
Geographic Range: This association has been reported only from north-central Colorado, northwestern Wyoming and south-central Montana, but it may occur elsewhere in alpine zones of the northern U.S. Rocky Mountains.

Nations: US

States/Provinces:  CO, WY


Confidence Level: Low

Confidence Level Comments: No Data Available
Grank: G3

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 A3155 Blackroot Sedge - Curly Sedge - Bellardi Bog Sedge Rocky Mountain Alpine Turf Alliance A3155 4.B.1.Nb.2.b
Association CEGL001970 Ross'' Avens - Clover species Alpine Turf CEGL001970 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: = Acomastylis rossii / Trifolium dasyphyllum Plant Association (Johnston 1987)
= Acomastylis rossii / Trifolium nanum Plant Association (Johnston 1987)
>< Acomastylis rossii / Trifolium sp. - Deschampsia cespitosa Plant Association (Johnston 1987) [Johnston states this is equivalent to Geum rossii - Trifolium parryi Community Type described by Thilenius and Smith (1985).]
< Carex - Geum Meadow Stand Type (Bamberg 1961)
> Geum rossii - Trifolium nanum Community Type (Thilenius and Smith 1985)
> Geum rossii - Trifolium parryi Community Type (Thilenius and Smith 1985)
= Geum rossii - Trifolium spp. (Jones and Ogle 2000)
< Geum Turf (Johnson and Billings 1962) [research from Beartooth Plateau in Montana and Wyoming. Many stands are codominated by Geum rossii and Carex rupestris var. drummondiana and may be better classified as ~Carex rupestris - Geum rossii Alpine Turf (CEGL001861)$$.]
> Trifolium dasyphyllum - Geum rossii Community Type (Thilenius and Smith 1985)
> Trifolium parryi - Acomastylis rossii Habitat Type Association (Komarkova 1986)
< Geum Turf (Smith 1969)
Concept Author(s): G.P. Jones

Author of Description: G.P. Jones and K.A. Schulz

Acknowledgements: No Data Available

Version Date: 01-13-05
  • Bamberg, S. A. 1961. Plant ecology of alpine tundra area in Montana and adjacent Wyoming. Unpublished dissertation, University of Colorado, Boulder. 163 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.
  • 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/]
  • Johnson, P. L., and W. D. Billings. 1962. The alpine vegetation of the Beartooth Plateau in relation to cryopedogenic processes and patterns. Ecological Monographs 32(2):105-133.
  • 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.
  • Jones, G., and S. Ogle. 2000. Characterization abstracts for vegetation types on the Bighorn, Medicine Bow, and Shoshone national forests. Prepared for USDA Forest Service, Region 2 by the Wyoming Natural Diversity Database, University of Wyoming.
  • Komarkova, V. 1986. Habitat types on selected parts of the Gunnison and Uncompahgre national forests. Unpublished final report prepared for USDA Forest Service, Rocky Mountain Forest and Range Experiment Station. Fort Collins, CO. 270 pp. plus appendices.
  • 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.).
  • Smith, D. R. 1969. Vegetation, soils and their interrelationships at timberline in the Medicine Bow Mountains, Wyoming. University of Wyoming Agricultural Experiment Station Science Monograph 17. 13 pp.
  • Thilenius, J. F., and D. R. Smith. 1985. Vegetation and soils of an alpine range in the Absaroka Mountains, Wyoming. General Technical Report RM-121. USDA Forest Service, Rocky Mountain Forest and Range Experiment Station, Fort Collins, CO. 18 pp.
  • Thilenius, J. F., and G. R. Brown. 1987. Herded vs. unherded sheep grazing systems on an alpine range in Wyoming. General Technical Report RM-147. USDA Forest Service, Rocky Mountain Forest and Range Experiment Station, Fort Collins, CO.
  • 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.