Print Report
A4022 Rocky Mountain Alpine Nonvascular Bedrock & Scree Alliance
Type Concept Sentence: This alpine alliance is characterized by sparse to moderately dense nonvascular cover (5-40%) composed of mostly lichens and mosses. Vascular vegetation (tree, shrub, herbaceous species) is absent or sparse (<5% cover). It is found throughout the Rocky Mountain cordillera and alpine areas in high plateaus and ranges in the Colorado Plateau and Great Basin on rocky scree slopes and boulderfields in the alpine extending down into the subalpine and montane zones.
Common (Translated Scientific) Name: Rocky Mountain Alpine Nonvascular Bedrock & Scree Alliance
Colloquial Name: Rocky Mountain Alpine Nonvascular Bedrock & Scree
Hierarchy Level: Alliance
Type Concept: Vegetation is characterized by sparse to moderately dense cover (5-40%) of nonvascular species (mostly lichens and mosses) on rocky substrates. Vascular vegetation is absent or sparse, with a few tree, shrub, herbaceous, and moss species growing in rock crevices at some sites with very low coverage (<5%) in openings between rocks. Species vary with site and size of microsite habitats. Nonvascular cover exceeds vascular plant cover. This sparsely vegetated alliance occurs throughout the Rocky Mountains cordillera and alpine areas in high plateaus and ranges in the Colorado Plateau and Great Basin from New Mexico north to central Alberta. Stands occur on rocky scree slopes and boulderfields in the alpine and extend down into the subalpine and montane zones.
Diagnostic Characteristics: Sites where vascular plant cover is <5% and nonvascular cover is dominant and characteristic.
Rationale for Nominal Species or Physiognomic Features: No Data Available
Classification Comments: More detailed information is lacking as bryophytic communities (nonvascular-dominated sites) on rock outcrops above and below treeline are poorly sampled throughout the U.S.
Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: No Data Available
Floristics: This alliance is characterized by sparse to moderate nonvascular cover (5-40%) that exceeds vascular cover. The nonvascular cover is composed of mostly lichens and mosses. Lichens are diverse. Common lichens on boulderfields are Buellia sp., Candelaria sp., Cladonia pyxidata, Lecidea atrobrunnea, Rhizocarpon geographicum, Rhizoplaca chrysoleuca (= Lecanora rubina), Umbilicaria proboscidea, Umbilicaria anthracina, Umbilicaria proboscidea, Xanthoparmelia conspersa (= Parmelia conspersa), Rusavskia elegans (= Caloplaca elegans), and on late-melting snowbeds sites Solorina crocea (Zinger and Willard 1996). Common and abundant bryophytes may include Aulacomnium palustre, Bryum spp., Hypnum revolutum, Philonotis fontana, Pohlia sp., Polytrichastrum alpinum, Polytrichum piliferum, and Philonotis fontana var. pumila (= Philonotis tomentella). Less common species may include Amphidium lapponicum, Grimmia elatior, Orthotrichum rupestre, Racomitrium sudeticum, and Schistidium apocarpum. Vascular vegetation (tree, shrub, herbaceous species) is absent or sparse (<5% cover) and does not exceed nonvascular cover. In the alpine, cushion plants are common, but vascular plants include a variety of species from the surrounding communities.
Dynamics: Alpine rock outcrops and boulderfields provide many microsites which allows for high species diversity.
Environmental Description: This alpine alliance is found throughout the Rocky Mountain cordillera and alpine areas in high plateaus and ranges in the Colorado Plateau and Great Basin. Stands occur on rocky scree slopes and boulderfields in the alpine extending down into the subalpine and montane zones. Sites are typically rocky and windswept, lacking protective cover of snow, but also include the centers of late-melt snowbeds where vascular plants do not have time to develop. In Colorado elevation ranges from 2360 to 4055 m. Substrates include a variety of rocks such as granite, gneiss, sandstone, etc.
Geographic Range: This alpine alliance is found throughout the Rocky Mountain cordillera and alpine areas in high plateaus and ranges in the Colorado Plateau and Great Basin from Alberta and British Columbia, Canada, south into New Mexico, and west into Nevada.
Nations: CA,US
States/Provinces: AB, AZ, BC, CO, MT, NM, NV, UT, WY
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.900073
Confidence Level: Low
Confidence Level Comments: No Data Available
Grank: GNR
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.c Eight-petal Mountain-avens - Saxifrage species Rocky Mountain Alpine Bedrock & Scree Group | G571 | 4.B.1.Nb.2.c |
| Alliance | A4022 Rocky Mountain Alpine Nonvascular Bedrock & Scree Alliance | A4022 | 4.B.1.Nb.2.c |
| Association | CEGL002888 Alpine Sparse (on rock & unconsolidated substrates) Nonvascular Vegetation | CEGL002888 | 4.B.1.Nb.2.c |
Concept Lineage: No Data Available
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: No Data Available
- Faber-Langendoen, D., J. Drake, M. Hall, G. Kittel, S. Menard, C. Nordman, M. Pyne, M. Reid, M. Russo, K. Schulz, L. Sneddon, K. Snow, and J. Teague. 2013-2019b. Screening alliances for induction into the U.S. National Vegetation Classification: Part 1 - Alliance concept review. NatureServe, Arlington, VA.
- Salas, D. E. 2002. USGS-NPS Vegetation Mapping Program, Fort Union Trading Post National Historic Site. Technical Memorandum 8260-02-08. USDI Bureau of Reclamation, Denver, CO. 128 pp.
- Zwinger, A. H., and B. E. Willard. 1996. Land above the trees: A guide to American alpine tundra. Johnson Books, Boulder, CO. 425 pp.