Print Report
A3331 Phyllodoce empetriformis - Cassiope mertensiana - Vaccinium deliciosum Alpine Dwarf-shrubland Alliance
Type Concept Sentence: Within these communities, dwarf-shrub is often the dominant lifeform, but they also occur with a mosaic of very low subshrub-like perennial- and herbaceous-dominated communities. Cassiope mertensiana, Luetkea pectinata, Phyllodoce empetriformis, Phyllodoce glanduliflora, or Vaccinium deliciosum may be the dominant. These dwarf-shrublands are typically located in subalpine or low alpine habitats on high mountains of the Pacific Northwest, often in association with subalpine parkland.
Common (Translated Scientific) Name: Pink Mountain-heath - Western Moss-heather - Cascade Bilberry Alpine Dwarf-shrubland Alliance
Colloquial Name: Pacific Northwest Mountain-heath Alpine Dwarf-shrubland
Hierarchy Level: Alliance
Type Concept: Within these communities, dwarf-shrub is often the dominant lifeform, but they also occur with a mosaic of very low subshrub-like perennials- and herbaceous-dominated communities. Cassiope mertensiana, Luetkea pectinata, Phyllodoce empetriformis, Phyllodoce glanduliflora, or Vaccinium deliciosum may be the dominant. Kalmia microphylla, Ledum glandulosum, Salix cascadensis, Vaccinium membranaceum, and Vaccinium scoparium may also be shrub associates. The herbaceous layer is usually a lush mix of forbs and graminoids, especially sedges, including, Antennaria lanata, Arenaria capillaris, Carex breweri, Carex nigricans, Carex phaeocephala, Carex scirpoidea, Carex spectabilis, Castilleja parviflora, Claytonia lanceolata, Deschampsia cespitosa, Erigeron spp., Erythronium spp., Festuca brachyphylla, Festuca viridula, Hieracium gracile, Juncus parryi, Juncus drummondii, Ligusticum grayi, Luetkea pectinata, Lupinus sellulus var. lobbii, Luzula piperi, Minuartia obtusiloba, Oreostemma alpigenum, Pedicularis ornithorhyncha, Polygonum bistortoides, Potentilla flabellifolia, Ranunculus eschscholtzii, Saxifraga tolmiei (which can be codominant with the dwarf-shrub layer), Sibbaldia procumbens, Tauschia stricklandii (a forb that can be the dominant in mosaic meadow patch), Valeriana sitchensis, and Veronica cusickii. Moss and lichen cover can be high in spaces between vascular plants (70-80%). These communities usually grade into herbaceous meadows dominated by Carex spp. at their wetter margin and, in stands below treeline, into woodlands of Tsuga mertensiana, Abies lasiocarpa, and/or Pinus albicaulis at their drier margins, and alpine fell-fields, rock, or ice on higher elevation alpine slopes. Such changes are generally related to only minor changes in microelevation, and woodland, dwarf-shrubland, and herbaceous meadow communities may be strongly intermingled. These dwarf-shrubland and herbaceous communities are typically located in subalpine or low alpine habitats on high mountains of the Pacific Northwest, often in association with subalpine parkland. Some of these dwarf-shrublands form part of a subalpine parkland mosaic just below the upper treeline. The climate is cold and snowy with annual precipitation exceeding 150 cm and a snow-free period of only 3-4 months. These habitats receive abundant (100-250 cm) precipitation and accumulate very heavy snowpacks in winter. These sites are subirrigated by snowmelt during most of the short growing season, although some meadows have soils that dry out by summer''s end. Elevations typically range from 1400-2500 m. These communities occur in areas of level or concave to very steep slopes (over 100%) on hills and ridges of glacial topography, with late-lying snow, and subirrigation from surrounding slopes. In exceptionally wet areas, they may occur on convex slopes with better drainage. Soils are moist, but well-drained, strongly acidic, and often with substantial peat layers. Some stands are found on the base of a lobe of soil formed by solifluction. Other are found on deep deposits of volcanic ash, such as thick accumulations of pumice parent material; some occur on andesite.
Diagnostic Characteristics: Within these communities, dwarf-shrub is the dominant lifeform. The dwarf-shrubs occur in a mosaic of very low subshrub-like perennials- and herbaceous-dominated communities. Cassiope mertensiana, Luetkea pectinata, Phyllodoce empetriformis, Phyllodoce glanduliflora, or Vaccinium deliciosum may be dominant.
Rationale for Nominal Species or Physiognomic Features: No Data Available
Classification Comments: This combines five former alliances and their associations (save two noted below): Cassiope mertensiana Dwarf-shrubland Alliance (A.1081), Luetkea pectinata - Saxifraga tolmiei Herbaceous Alliance (A.1629), Phyllodoce empetriformis Dwarf-shrubland Alliance (A.1083), Phyllodoce glanduliflora Dwarf-shrubland Alliance (A.1084), Vaccinium deliciosum Dwarf-shrubland Alliance (A.1115), and Tauschia stricklandii Herbaceous Alliance (A.1655). A new alliance is needed for these Rocky Mountain associations: ~Phyllodoce empetriformis / Antennaria lanata Dwarf-shrubland (CEGL001405)$$ occurs in Montana and ~Phyllodoce glanduliflora / Sibbaldia procumbens Dwarf-shrubland (CEGL005877)$$ occurs in Alberta and Montana. This is also inclusive of the Cassiope mertensiana and Luetkea pectinata alliances proposed by the Alaska Natural Heritage Program.
Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: These communities are characterized by a semi-continuous layer of ericaceous dwarf-shrubs, which form a heath type ground cover less than 0.5 m in height. Dense turfs of graminoids and scattered forbs occur, under the dwarf-shrub layer and in small breaks in the shrub canopy.
Floristics: Within these communities, dwarf-shrub is often the dominant lifeform, but they also occur with a mosaic of very low subshrub-like perennials- and herbaceous-dominated communities. Cassiope mertensiana, Luetkea pectinata, Phyllodoce empetriformis, Phyllodoce glanduliflora, or Vaccinium deliciosum may be the dominant dwarf-shrub. Kalmia microphylla, Ledum glandulosum, Salix cascadensis, Vaccinium membranaceum, and Vaccinium scoparium may also be shrub associates. The herbaceous layer is usually a lush mix of forbs and graminoids, especially sedges, including, Antennaria lanata, Arenaria capillaris, Carex breweri, Carex nigricans, Carex phaeocephala, Carex scirpoidea, Carex spectabilis, Castilleja parviflora, Claytonia lanceolata, Deschampsia cespitosa, Erigeron spp., Erythronium spp., Festuca brachyphylla, Festuca viridula, Hieracium gracile, Juncus parryi, Juncus drummondii, Ligusticum grayi, Luetkea pectinata, Lupinus sellulus var. lobbii, Luzula piperi, Minuartia obtusiloba (= Arenaria obtusiloba), Oreostemma alpigenum (= Aster alpigenus), Pedicularis ornithorhyncha, Polygonum bistortoides, Potentilla flabellifolia, Ranunculus eschscholtzii, Saxifraga tolmiei (which can be codominant with the dwarf-shrub layer), Sibbaldia procumbens, Tauschia stricklandii (a forb that can be the dominant in mosaic meadow patch), Valeriana sitchensis, and Veronica cusickii. Moss and lichen cover can be high in spaces between vascular plants (70-80%).
Dynamics: These communities are associated with frigid, wet, nutrient-poor acidic soils, often derived from volcanic ash, which inhibit decomposition and accumulate organic matter. Such acidic soils favor persistence of ericaceous shrubs, resulting in stable stands. Cassiope mertensiana is sensitive to fire and burning usually results in seral communities dominated by Vaccinium spp. or Carex spp.
Environmental Description: The climate is cold and snowy with annual precipitation exceeding 150 cm and a snow-free period of only 3-4 months. These habitats receive abundant (100-250 cm) precipitation and accumulate very heavy snowpacks in winter. These sites are subirrigated by snowmelt during most of the short growing season, although some meadows have soils that dry out by summer''s end. Elevations typically range from 1400-2500 m. These communities occur in areas of level or concave to very steep slopes (over 100%) on hills and ridges of glacial topography, with late-lying snow, and subirrigation from surrounding slopes. In exceptionally wet areas, they may occur on convex slopes with better drainage. Soils are moist, but well-drained, strongly acidic, and often with substantial peat layers. Some stands are found on the base of a lobe of soil formed by solifluction. Others are found on deep deposits of volcanic ash, such as thick accumulations of pumice parent material; some occur on andesite.
Geographic Range: This alliance has been reported primarily from the higher mountains of Oregon and Washington, Alaska, and British Columbia, Canada, and in the mountains of northern Idaho and northern California. The range may extend south into the Klamath Mountains and Sierra Nevada of California.
Nations: CA,US
States/Provinces: AK, BC, CA, ID, OR, WA
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.899455
Confidence Level: Low
Confidence Level Comments: No Data Available
Grank: GNR
Greasons: No Data Available
Concept Lineage: This combines 5 former alliances (A.1081, A.1083, A.1115, A.1084, A.1655) and their associations [see Classification Comments].
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: ? Cassiope mertensiana (White mountain heather heath) Provisional Alliance (Sawyer et al. 2009) [91.126.00]
? Phyllodoce empetriformis (Mountain heather mats) Provisional Alliance (Sawyer et al. 2009) [45.404.00]
? Phyllodoce empetriformis (Mountain heather mats) Provisional Alliance (Sawyer et al. 2009) [45.404.00]
- Barbour, M. G., and J. Major, editors. 1977. Terrestrial vegetation of California. John Wiley and Sons, New York. 1002 pp.
- 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.
- Sawyer, J. O., T. Keeler-Wolf, and J. Evens. 2009. A manual of California vegetation. Second edition. California Native Plant Society, Sacramento CA. 1300 pp.