Alpine - Subalpine Herbaceous and Dwarf-Shrub Riparian and Wetland
Global Name:
Vancouverian-Rocky Mountain Subalpine-Alpine Snowbed, Wet Meadow & Dwarf-shrubland
Global Rank:
G4G5
State Rank:
S3S4
(see reason below)
External Links
State Rank Reason
These high elevation, riparian sites occur across the higher mountain ranges of the state but occupy relatively limited areas and are vulnerable to decreases in winter snowpack, drought and changes in precipitation patterns, and increased temperatures.
General Description
This National Vegetation Classification Group is composed of upper subalpine and alpine herbaceous and dwarf-shrub communities. They found on wet sites in the higher mountains of northwestern, southwest and south-central Montana. The elevations range from as low as 6,000 feet in northwestern Montana to 10,500 feet in southwestern Montana. The climate is very cold, with heavy snow accumulation and a very short growing season (60 to 90 days). These types occur as wet meadows, as narrow strips bordering ponds, lakes and streams, and along toeslope seeps. These communities may be dominated by a variety of wet site herbaceous communities as well as wetland sites dominated by dwarf-shrublands. These sometimes take the form of rings of different plant communities around a late-melting snowbed with drier turf species on the outside edges, wetland species near the middle and sometimes a sparsely vegetated center as a result of the extremely short growing season. These sites are tightly associated with snowmelt and typically not subjected to high disturbance events such as flooding.
This group includes the higher elevation communities included in the Alpine-Montane Wet Meadow Ecological System.
Diagnostic Characteristics
Upper Subalpine and Alpine Zones; Wet sites, Wetland Communities, Snowbed Communities; Vegetation Cover >15%; Herbaceous Vegetation, Dwarf Shrubs, Subshrubs; Short Growing Season.
Similar Systems
Range
This group occurs in many of the higher elevation mountain ranges in northwestern, southwest and south-central Montana that have significant, vegetated, alpine areas above treeline. This includes many areas along and west of the Continental Divide and the higher ranges east of the Continental Divide such as the East Pioneers, Tobacco Root Mtns, the Crazy Mtns and mountainous areas south of these ranges.
In Montana, G520 is confined to areas within or immediately adjacent to Level IV Ecoregions 15h (High Northern Rockies), 16h (High Idaho Batholith), 17h (Middle Rockies Alpine Zone) and 41b Canadian Rockies Crestal Alpine-Subalpine Zone.
In Montana, G520 occurs within these Major Land Resource Areas: 43A-Northern Rocky Mountains and 43B-Central Rocky Mountains.
Density and Distribution
Based on 2025 land cover layer. Grid on map is based on USGS 7.5 minute quadrangle map boundaries.
Mapped Distribution by County
Beaverhead, Carbon, Deer Lodge, Fergus, Flathead, Gallatin, Glacier, Golden Valley, Granite, Lake, Lewis and Clark, Madison, Missoula, Park, Pondera, Powell, Ravalli, Stillwater, Sweet Grass, Teton
Based on 2025 land cover layer.
Spatial Pattern
Small Patch
Environment
This group occurs in the upper subalpine and alpine zones. The elevation ranges from as low as 6,000 feet in northwestern Montana to 10,500 feet in southwestern Montana. The climate is very cold, with heavy snow accumulation and a very short growing season (60 to 90 days). These types occur as meadows, as narrow strips bordering ponds, lakes and streams, and along toeslope seeps. They are typically found on flat areas or gentle slopes but may also occur on sub-irrigated sites with slopes up to 10%. In alpine regions, sites typically are small depressions located below late-melting snow patches or on snowbeds. Moisture for these wet meadow community types is acquired from groundwater, stream discharge, overland flow, overbank flow, and on-site precipitation. Depending on the slope, topography, hydrology, soils and substrate, intermittent, ephemeral or permanent pools may be present. Water tables typically remain at or near the soil surface though fluctuations of the water table throughout the growing season are not uncommon.
Soils of this group are mineral often with a thin (<40 cm) organic layer over the mineral layers. As a result, they are not classified as peatlands. Soils show hydric soil characteristics, often including high organic content and/or low chroma and redoximorphic features including gleying and/or mottling throughout the profile. Soils typically possess a high proportion of organic matter, but this may vary considerably depending on the frequency and magnitude of alluvial deposition (Kittel et. al. 1999b). Organic composition of the soil may include a thin layer near the soil surface or accumulations of highly sapric (mucky) material. Environmental information compiled in part from Willard (1963), Cooper (1986), Zwinger and Willard (1996), Cooper et al. (1997).
Vegetation
This group includes open to dense, graminoid- and forb-dominated, wet herbaceous communities as well as wetland sites dominated by dwarf-shrublands. These sometimes take the form of rings of different plant communities around a late-melting snowbed with drier turf species on the outside edges, wetland species near the middle and sometimes a sparsely vegetated center as a result of the extremely short growing season.
This group often occurs as a mosaic of several plant associations, often dominated by graminoids including Carex illota, Carex lachenalii, Carex nigricans, Deschampsia cespitosa, Phippsia algida, Juncus drummondii, Juncus mertensianus, and the forbs Caltha leptosepala, Trollius laxus, Parnassia fimbriata, Polygonum bistortoides, Sibbaldia procumbens, and Trifolium parryi. Scattered to moderately dense dwarf or low shrubs are occasionally present, including Shrubby Cinquefoil (Dasiphora fruticosa), Alpine Bog Laurel (Kalmia microphylla), or Bog Blueberry (Vaccinium uliginosum). Willow species such as Salix glauca, Salix planifolia, and Salix reticulata may also be present. (Cooper etal. 1997).
In Montana, this group is represented by 8 Associations grouped into 4 Alliances within the National Vegetation Classification, though 1 Alliance has no Associations attributed for the state. Additional work is needed to clarify the Alliances and Associations that occur in Montana.
National Vegetation Classification
Download the complete NVC hierarchy for Montana
TP1 B08 Palustrine Wetland
TP1.b S70 Emergent Open Wetland
TP1.b1 F137 Marsh, Wet Meadow and Shrub Wetland
TP1.b1.Ne D031 Western North American Temperate Freshwater Marsh, Wet Meadow and Shrubland
TP1.b1.Ne.4 M893 Western North American Montane Marsh, Wet Meadow and Shrubland
TP1.b1.Ne.4.c G520 Pacific-Rocky Mountain Subalpine-Alpine Snowbed and Wet Meadow
A1698 Caltha leptosepala - Rhodiola rhodantha Wet Meadow Alliance
CEGL001954 Caltha leptosepala Wet Meadow
A3831 Kalmia microphylla - Cassiope mertensiana - Dryas drummondii Wet Dwarf-shrubland Alliance
CEGL001396 Cassiope mertensiana / Carex paysonis Wet Dwarf-shrubland
CEGL001402 Kalmia microphylla / Carex nigricans Wet Dwarf-shrubland
CEGL001403 Kalmia microphylla / Carex scopulorum Wet Dwarf-shrubland
CEGL005834 Dryas drummondii / Chamerion latifolium Wet Dwarf-shrubland
A3832 Carex nigricans - Sibbaldia procumbens - Trollius laxus Wet Meadow Alliance
CEGL001816 Carex nigricans Wet Meadow
CEGL005824 Carex nigricans - Sibbaldia procumbens Wet Meadow
CEGL005858 Trollius laxus - Parnassia fimbriata Wet Meadow
A4417 Mimulus lewisii - Philonotis fontana Seep and Streambank Alliance
*Disclaimer: Some Alliances and Associations are considered provisional. Some require further documentation to verify their occurrence in the state
and some may be modified or deleted in future revisions after collection of additional data and information.
Dynamic Processes
These sites are tightly associated with snowmelt and typically not subjected to high disturbance events such as flooding. Due to the mesic setting of these communities along with the patchiness of the vegetation, fires are not an important process.
Management
Depending on the particular setting and scope of the wetland plant community, critical functions may include water filtration, flow attenuation, and wildlife habitat functions. These communities are fragile due to the very limited growing season and limited soil development. Species that occur on these sites are generally slow growing and decrease in cover and vigor in areas of trampling.
Species Associated with this Community
- How Lists Were Created and Suggested Uses and Limitations
Animal Species Associations
Please note that while all vertebrate species have been systematically associated with vegetation communities, only a handful of invertebrate species have been associated with vegetation communities and invertebrates lists for each vegetation community should be regarded as incomplete. Animal species associations with natural vegetation communities that they regularly breed or overwinter in or migrate through were made by:
- Using personal observations and reviewing literature that summarize the breeding, overwintering, or migratory habitat requirements of each species (Dobkin 1992, Hart et al. 1998, Hutto and Young 1999, Maxell 2000, Werner et al. 2004, Adams 2003, and Foresman 2012);
- Evaluating structural characteristics and distribution of each vegetation community relative to the species' range and habitat requirements;
- Examining the observation records for each species in the state-wide point observation database associated with each vegetation community;
- Calculating the percentage of observations associated with each vegetation community relative to the percent of Montana covered by each vegetation community to get a measure of "observations versus availability of habitat".
Species that breed in Montana were only evaluated for breeding habitat use. Species that only overwinter in Montana were only evaluated for overwintering habitat use. Species that only migrate through Montana were only evaluated for migratory habitat use. In general, species are listed as associated with a vegetation community if it contains structural characteristics known to be used by the species. However, species are not listed as associated with a vegetation community if we found no support in the literature for the species’ use of structural characteristics of the community even if point observations were associated with it. If you have any questions or comments on animal species associations with vegetation communities, please contact the Montana Natural Heritage Program's Senior Zoologist.
Plant Species Associations
Please note that while diagnostic, dominant, or codominant vascular plant species for a vegetation community have been systematically assigned to those communities and vascular plant Species of Concern were systematically evaluated for their associations with vegetation communities, the majority of Montana’s vascular plant species have not been evaluated for their associations with vegetation communities and no attempt has been made to associate non-vascular plants, fungi, or lichens with vegetation communities. Plant species associations with natural vegetation communities were made in a manner similar to that described above for animals, but with review of Lesica et al. (2022) and specimen collection data from the Consortium of Pacific Northwest Herbaria. If you have any questions or comments on plant species associations with vegetation communities, please contact the Montana Natural Heritage Program's Program Botanist.
Suggested Uses and Limitations
Species associations with vegetation communities should be used to generate potential lists of species that may occupy broader landscapes for the purposes of landscape-level planning. These potential lists of species should not be used in place of documented occurrences of species or predicted habitat suitability models (this information can be requested at: https://mtnhp.mt.gov/requests/), or systematic surveys for species and onsite evaluations of habitat by trained biologists. Users of this information should be aware that the land cover data used to generate species associations is based on satellite imagery from 2016 and was only intended to be used at broader landscape scales. Land cover mapping accuracy is particularly problematic when the vegetation communities occur as small patches or where the land cover types have been altered over the past decade. Thus, particular caution should be used when using the associations in assessments of smaller areas (e.g., evaluations of public land survey sections). Finally, although a species may be associated with a particular vegetation community within its known geographic range, portions of that vegetation community may occur outside of the species' known geographic range.
Literature Cited
- Adams, R.A. 2003. Bats of the Rocky Mountain West; natural history, ecology, and conservation. Boulder, CO: University Press of Colorado. 289 p.
- Consortium of Pacific Northwest Herbaria. https://www.pnwherbaria.org/ Last accessed May 30, 2025.
- Dobkin, D. S. 1992. Neotropical migrant land birds in the Northern Rockies and Great Plains. USDA Forest Service, Northern Region. Publication No. R1-93-34. Missoula, MT.
- Foresman, K.R. 2012. Mammals of Montana. Second edition. Mountain Press Publishing, Missoula, Montana. 429 pp.
- Hart, M.M., W.A. Williams, P.C. Thornton, K.P. McLaughlin, C.M. Tobalske, B.A. Maxell, D.P. Hendricks, C.R. Peterson, and R.L. Redmond. 1998. Montana atlas of terrestrial vertebrates. Montana Cooperative Wildlife Research Unit, University of Montana, Missoula, MT. 1302 p.
- Hutto, R.L. and J.S. Young. 1999. Habitat relationships of landbirds in the Northern Region, USDA Forest Service, Rocky Mountain Research Station RMRS-GTR-32. 72 p.
- Lesica P., M. Lavin, and P.F. Stickney. 2022. Manual of vascular plants, 2nd Edition. Brit Press. 779 p.
- Maxell, B.A. 2000. Management of Montana's amphibians: a review of factors that may present a risk to population viability and accounts on the identification, distribution, taxonomy, habitat use, natural history, and the status and conservation of individual species. Report to U.S. Forest Service Region 1. Missoula, MT: Wildlife Biology Program, University of Montana. 161 p.
- Werner, J.K., B.A. Maxell, P. Hendricks, and D. Flath. 2004. Amphibians and reptiles of Montana. Missoula, MT: Mountain Press Publishing Company. 262 p.
- Species of Concern Associated with this Community
Vascular Plants
Mammals
Birds
Reptiles
Amphibians
Invertebrates
- Diagnostic, Dominant, or Codominant Plant Species for this Community
Vascular Plants
- Other Native Species Commonly Associated with this Community
Vascular Plants
- Other Native Species Occasionally Associated with this Community
Amphibians
Original Concept Authors
K.A. Schulz 2015
Montana Version Authors
S. Mincemoyer, L. Vance, C. McIntyre, T. Luna
Version Date
11/25/2024
References
- Literature Cited AboveLegend:
View Online Publication
Cooper, D. J. 1986b. Community structure and classification of Rocky Mountain wetland ecosystems. Pages 66-147 in: J. T. Windell, et al. An ecological characterization of Rocky Mountain montane and subalpine wetlands. USDI Fish & Wildlife Service Biological Report 86(11). 298 pp.- Cooper, Stephen V., Peter Lesica, and Deborah S. Page-Dumroese. 1995. Plant community classification for alpine vegetation on the Beaverhead National Forest, Montana. Ogden, UT (324 25th Street, Ogden 84401): U.S. Dept. of Agriculture, Forest Service, Intermountain Research Station.
- Kittel, G., E. Van Wie, M. Damm, R. Rondeau, S. Kettler, A. McMullen, and J. Sanderson. 1999. A classification of riparian and wetland plant associations of Colorado: A user's guide to the classification project. Colorado Natural Heritage Program, Colorado State University, Fort Collins CO. 70 pp. plus appendices.
- Willard, B.E. 1963. Phytosociology of the alpine tundra of Trail Ridge, Rocky Mountain National Park, Colorado. Unpublished dissertation, University of Colorado, Boulder.
- Zwinger, A. H., and B. E. Willard. 1996. Land above the trees: A guide to American alpine tundra. Johnson Books, Boulder, CO. 425 pp.
- Additional ReferencesLegend: View Online Publication
Do you know of a citation we're missing?- Pojar J., and A. MacKinnon. 2013. Alpine Plants of the Northwest: Wyoming to Alaska. Lone Pine Publishing. Edmonton, AB, Canada. 527pp.
- Web Search Engines for Articles on "Vancouverian-Rocky Mountain Subalpine-Alpine Snowbed, Wet Meadow & Dwarf-shrubland"
