Print Report

G356 Betula nana - Salix pulchra Mesic Low Shrubland Group

Type Concept Sentence: This group is defined by birch shrublands occurring on mesic, mid-to upper slope sites throughout boreal and subboreal Alaska. The primary species is Betula glandulosa which often forms extensive thickets with other low ericaceous shrubs and Salix species near treeline.

Common (Translated Scientific) Name: Dwarf Birch - Tealeaf Willow Mesic Low Shrubland Group

Colloquial Name: Western Boreal Mesic Birch - Willow Low Shrubland

Hierarchy Level:  Group

Type Concept: This shrubland group occurs on mesic, mid- to upper-slope sites throughout the boreal and subboreal regions of Alaska and is often matrix-forming above coniferous treeline. Betula glandulosa dominates in the boreal with dominance transitioning to Betula nana in the subboreal region of southwest Alaska. Vaccinium uliginosum and Ledum palustre ssp. decumbens both have high constancy and canopy cover and may occasionally be canopy dominants. Other common shrubs include Salix pulchra and Salix glauca. Dwarf-shrubs, including Vaccinium vitis-idaea and Empetrum nigrum, may be common below the low-shrub layer. Herbaceous species are sparse and may include Calamagrostis canadensis, Carex bigelowii, Rubus chamaemorus, and Chamerion angustifolium ssp. angustifolium. Feathermosses such as Hylocomium splendens and Pleurozium schreberi, lichens in the genus Cladonia, and Sphagnum species are common in the ground layer. Wetland sites with organic soils are not included in this group.

Diagnostic Characteristics: This group is defined as a boreal to subboreal shrubland dominated by Betula glandulosa in the boreal with dominance transitioning to Betula nana in the subboreal region of southwest Alaska. Diagnostic species include Betula glandulosa, Vaccinium uliginosum, Ledum palustre ssp. decumbens, and Vaccinium vitis-idaea.

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: Betula glandulosa is dominant in the continental boreal, while Betula nana becomes more common in the subboreal region of southwest Alaska which is beyond the central range of Betula glandulosa.

Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: This group represents deciduous shrublands with variable stand height and a sparse herbaceous layer.

Floristics: Betula glandulosa or Betula nana often dominates the shrub layer with Betula glandulosa dominating in the boreal with dominance transitioning to Betula nana in the subboreal region of southwest Alaska. Betula glandulosa is described as a low-shrub species; however, shrub height is variable, and sites with shrubs greater than 1.5 m are reported. Other shrubs with high constancy include Vaccinium uliginosum, Ledum palustre ssp. decumbens, Salix pulchra, and Salix glauca. Dwarf-shrubs, including Vaccinium vitis-idaea and Empetrum nigrum, may be common below the low-shrub layer. Herbaceous species are sparse and may include Calamagrostis canadensis, Carex bigelowii, Rubus chamaemorus, and Chamerion angustifolium ssp. angustifolium. Feathermosses such as Hylocomium splendens and Pleurozium schreberi, lichens in the genus Cladonia, and Sphagnum species are common in the ground layer.

Dynamics:  This group represents a topo-edaphic climax in some areas; in other cases it may be seral to shrub-tussock over long time periods. There is little information available regarding the fire history of shrub communities in Alaska. After fire, shrubs readily resprout from underground propagules if they have not been burned, and a shrub community may re-establish within five years. After severe fires that burn both the organic layer and propagules, herbaceous species that establish by seed may dominate the site for more than five years. Burned spruce woodlands near treeline may be converted to low shrub after fire (Pegau 1972), which may slowly regenerate a spruce overstory. Adjacent vegetation influences the fire frequency. If the adjacent vegetation is flammable, then low-shrub types will have a more frequent fire return. Without adjacent flammable vegetation, fire-return intervals are likely to exceed 100 years. The fire-return interval is longer in the boreal transition region than in boreal Alaska.
Environmental Description:  This group occurs on mesic to moist slopes and terraces often in the subalpine. Soils are mineral with a well-decomposed organic layer 5-30 cm thick.
Geographic Range: This group occurs in the boreal and subboreal transition regions of Alaska from low elevations to above treeline.

Nations: CA,US

States/Provinces:  AK, BC, YT


Confidence Level: Moderate

Confidence Level Comments: No Data Available
Grank: GNR

Greasons: No Data Available
Type Name Database Code Classification Code
Class 2 Shrub & Herb Vegetation Class C02 2
Subclass 2.B Temperate & Boreal Grassland & Shrubland Subclass S18 2.B
Formation 2.B.3 Boreal Grassland & Shrubland Formation F028 2.B.3
Division 2.B.3.Na North American Boreal Grassland & Shrubland Division D025 2.B.3.Na
Macrogroup 2.B.3.Na.1 North American Boreal Shrubland & Grassland Macrogroup M055 2.B.3.Na.1
Group 2.B.3.Na.1.f Dwarf Birch - Tealeaf Willow Mesic Low Shrubland Group G356 2.B.3.Na.1.f
Alliance A4274 Dwarf Birch - Tealeaf Willow - Marsh Labrador-tea Low Shrubland Alliance A4274 2.B.3.Na.1.f
Alliance A4275 Tealeaf Willow / Bluejoint Low Shrubland Alliance A4275 2.B.3.Na.1.f
Concept Lineage: No Data Available

Predecessors: No Data Available

Obsolete Names: No Data Available

Obsolete Parents: No Data Available
Synonomy: > Vaccinium uliginosum / Low shrub (Bog blueberry / Low shrub) (Boggs et al. 2003)
>< II.C.1.a - Shrub birch (Viereck et al. 1992)
= II.C.2.c - Mesic shrub birch-ericaceous shrub (Viereck et al. 1992)
Concept Author(s): Western Ecology Group and Alaska Natural Heritage Program

Author of Description: T.V. Boucher

Acknowledgements: Mark Hall, Lindsey Flagstad

Version Date: 01-19-16
  • Anderson, J. H. 1974. Plants, soils, phytocenology and primary production of the Eagle Summit Tundra Biome Site. U.S. Tundra Biome Data Report 74-42. Ecosystem Analysis Studies, U.S. International Biological Program, U.S. Arctic Research Program. 142 pp.
  • Batten, A. R. 1977. The vascular floristics, major vegetation units, and phytogeography of the Lake Peters area, northeastern Alaska. M.S. thesis, University of Alaska, Fairbanks. 330 pp.
  • Batten, A. R., D. F. Murray, and J. C. Dawe. 1979. Threatened and endangered plants in selected areas of the BLM Fortymile Planning Unit. File report for Contract No. YA-512-CT8-162. USDI Bureau of Land Management, Alaska State Office, Anchorage. 127 pp.
  • Boggs, K. W., S. C. Klein, J. E. Grunblatt, and B. Koltun. 2003. Landcover classes, ecoregions and plant associations of Katmai National Park and Preserve. Natural Resource Technical Report NPS/KATM/NRTR--2003/001. National Park Service, Fort Collins, CO. 274 pp.
  • Faber-Langendoen, D., J. Drake, S. Gawler, M. Hall, C. Josse, G. Kittel, S. Menard, C. Nordman, M. Pyne, M. Reid, L. Sneddon, K. Schulz, J. Teague, M. Russo, K. Snow, and P. Comer, editors. 2010-2019a. Divisions, Macrogroups and Groups for the Revised U.S. National Vegetation Classification. NatureServe, Arlington, VA. plus appendices. [in preparation]
  • Hanson, H. C. 1951. Characteristics of some grassland, marsh and other plant communities in western Alaska. Ecological Monographs 21(4):318-373.
  • Hanson, H. C. 1953. Vegetation types in northwestern Alaska and comparisons with communities in other arctic regions. Ecology 34(1):111-140.
  • Hettinger, L. R., and A. J. Janz. 1974. Vegetation and soils of northeastern Alaska. Arctic Gas Biological Report Series 21, Northern Engineering Services Company, Ltd., Edmonton, Canada. 206 pp.
  • Hulten, E. 1966. Contributions to the knowledge of flora and vegetation of the southwestern Alaskan mainland. Svensk Botanisk Tidskrift 60(1):175-1 89.
  • Jorgenson, M. T. 1984. The response of vegetation to landscape evolution on glacial till near Toolik Lake, Alaska. Pages 134-142 in: Inventorying forest and other vegetation of the high latitude and high altitude regions. Proceedings of an International Symposium, Society of American Foresters Regional Technical Conference. Fairbanks, AK. Society of American Foresters, Bethesda, MD.
  • Kessel, B., and G. B. Schaller. 1960. Birds of the upper Sheenjek Valley, northeastern Alaska. Biological Paper 4, University of Alaska, Fairbanks. 59 pp.
  • Pegau, R. E. 1968. Reindeer range appraisal in Alaska. M.S. thesis, University of Alaska, Fairbanks. 130 pp.
  • Pegau, R. E. 1972. Caribou investigations-analysis of range. Pages 1-216 in: R. E. Pegau and J. E. Hemming, editors. Caribou report. Volume 12. Progress report. Federal Aid in Wildlife Restoration, Projects W-17-2 and W-17-3, Job 3.3R. Alaska Department of Fish and Game, Juneau, AK.
  • Racine, C. H. 1979. Climate of the Chucki-Imuruk area. Pages 32-37 in: H. R. Melchior, editor. Biological Survey of the Bering Land Bridge National Monument. Alaska Cooperative Park Studies Unit, University of Alaska, Fairbanks.
  • Shiflet, T. N., editor. 1994. Rangeland cover types of the United States. Society for Range Management. Denver, CO. 152 pp.
  • Steigers, W. D., D. Helm, J. G. MacCracken [and others]. 1983. Alaska Power Authority, Susitna Hydroelectric Authority, environmental studies--subtask 7.12: 1982 plant ecology studies. Final report. Agricultural Experiment Station, University of Alaska, Palmer. 288 pp.
  • Viereck, L. A. 1962. Range survey: Sheep and goat investigations. Job completion report: Federal aid in wildlife restoration. W-6-R-3. Department of Fish and Game, Alaska work plan E, Job 2a. 21 pp.
  • Viereck, L. A. 1963. Sheep investigations: Survey of range ecology. Project W-6-R-4, Work plan E. Job 2-A. Alaska Department of Fish and Game, Juneau.
  • Viereck, L. A. 1966. Plant succession and soil development on gravel outwash on the Muldrow Glacier, Alaska. Ecological Monographs 36(3):181-199.
  • Viereck, L. A. 1979. Characteristics of treeline plant communities in Alaska. Holarctic Ecology 2:228-238.
  • Viereck, L. A., C. T. Dyrness, A. R. Batten, and K. J. Wenzlick. 1992. The Alaska vegetation classification. General Technical Report PNW-GTR286. USDA Forest Service, Pacific Northwest Research Station, Portland, OR. 278 pp.
  • Viereck, L. A., and E. L. Little. 1972. Alaska trees and shrubs. USDA Forest Service Agricultural Handbook 410. University of Alaska Press, Fairbanks. 265 pp.
  • Webber, P. J., V. Komarkova, D. A. Walker, and E. Werbe. 1978. Vegetation mapping and response to disturbance along the Yukon River-Prudhoe Bay Haul Road. Pages 25-87 in: J. Brown, principal investigator. Ecological baseline investigations along the Yukon River-Prudhoe Bay Haul Road, Alaska. Corps of Engineers, U.S. Army Cold Region Research and Engineering Laboratory, Hanover, NH.
  • Young, S. B., and C. H. Racine. 1978. Ecosystems or the proposed Katmai western extension, Bristol Bay Lowlands, Alaska. Final report. Contributions from the Center for Northern Studies, Wolcott, VT. 94 pp.