Print Report

CEGL003434 Ledum glandulosum / Carex obnupta / Sphagnum spp. Fen

Type Concept Sentence: No Data Available

Common (Translated Scientific) Name: Western Labrador-tea / Slough Sedge / Peatmoss species Fen

Colloquial Name: No Data Available

Hierarchy Level:  Association

Type Concept: Distinguished from similar associations farther north by the dominance of Ledum glandulosum instead of Ledum groenlandicum, this vegetation occurs only between the Columbia River and northern California. This early-seral association occurs in open mire complexes in poorly drained basins, valleys, and on floating lake mats. Circular or elliptical hummocks 1-3 feet taller than the surrounding mire surface form islands of ombrotrophic vegetation in otherwise minerotrophic mire fed by springs, runoff, or lakewater. Mature trees are absent, but reproducing Thuja plicata and Pinus contorta var. contorta occur in about half the plots and are slow-growing and stunted, most dying before maturity. The shrub layer is dominated by Ledum glandulosum with up to 60% cover. Kalmia microphylla or Vaccinium uliginosum are occasional. Two distinct variants occur with either Sphagnum palustre or Sphagnum fuscum dominant in the moss layer. The herb layer in the Sphagnum palustre variant typically contains 15-25 species and is characterized by Vaccinium oxycoccos, Drosera rotundifolia, Lysichiton americanus, Eriophorum chamissonis, Trientalis europaea ssp. arctica, Carex echinata ssp. phyllomanica, and Carex leptalea. The herb layer in the Sphagnum fuscum variant is conspicuously dwarfed and species-poor (10 or fewer) because of high acidity and low nutrient status. Hollows between hummocks in both variants are generally wet, species-poor, and consist almost entirely of lawns of Sphagnum angustifolium, Sphagnum pacificum, or bare muddy bottoms if trailed by elk and deer.

Diagnostic Characteristics: No Data Available

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: This association is treated here as one type with two variants (Sphagnum palustre or Sphagnum fuscum) instead of two separate associations as described in Christy (2001a). Carex obnupta, while present with a constancy of less than 80% and an average cover of less than 50%, is a diagnostic component of low-elevation Sphagnum mires and for this reason is included in the association name. It may occur with cover up to 45%.

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

Floristics: No Data Available

Dynamics:  No Data Available
Environmental Description:  No Data Available
Geographic Range: This association is restricted to the coast of Oregon between the Columbia River and northern California. Historically, it was reported as far south as San Francisco Bay and Fort Bragg, but has disappeared from many historic localities.

Nations: US

States/Provinces:  CA?, OR


Confidence Level: Moderate

Confidence Level Comments: No Data Available
Grank: G2

Greasons: No Data Available
Type Name Database Code Classification Code
Class 2 Shrub & Herb Vegetation Class C02 2
Subclass 2.C Shrub & Herb Wetland Subclass S44 2.C
Formation 2.C.2 Temperate to Polar Bog & Fen Formation F016 2.C.2
Division 2.C.2.Na North American Bog & Fen Division D029 2.C.2.Na
Macrogroup 2.C.2.Na.3 Beach Pine / Bog Labrador-tea / Cusick''s Sedge North Pacific Bog & Fen Macrogroup M063 2.C.2.Na.3
Group 2.C.2.Na.3.b North Pacific Acidic Open Bog & Fen Group G284 2.C.2.Na.3.b
Alliance A2514 Western Labrador-tea - Bog Labrador-tea Shrub Bog & Acidic Fen Alliance A2514 2.C.2.Na.3.b
Association CEGL003434 Western Labrador-tea / Slough Sedge / Peatmoss species Fen CEGL003434 2.C.2.Na.3.b
Concept Lineage: No Data Available

Predecessors: No Data Available

Obsolete Names: No Data Available

Obsolete Parents: No Data Available
Synonomy: = Ledum glandulosum / Carex obnupta / Sphagnum Association (Christy 2004)
? Ledum groenlandicum - Gaultheria shallon / Sphagnum spp. variant (Kunze 1994)
Concept Author(s): J.A. Christy

Author of Description: J.A. Christy

Acknowledgements: No Data Available

Version Date: 10-21-02
  • Christy, J. A. 2001a. Low-elevation Sphagnum wetlands in western Oregon. Report to Environmental Protection Agency, Region 10. Oregon Natural Heritage Program, Portland. 90 pp.
  • Christy, J. A. 2004. Native freshwater wetland plant associations of northwestern Oregon. Oregon Natural Heritage Information Center, Oregon State University, Portland, OR.
  • Christy, J. A., and L. Brophy. 2002. Vegetation of Neskowin Marsh Unit, Nestucca Bay National Wildlife Refuge, Tillamook County, Oregon. Report to U.S. Fish and Wildlife Service. Oregon Natural Heritage Information Center and Green Point Consulting. 26 pp.
  • Hansen, H. P. 1941a. Paleoecology of two peat deposits on the Oregon coast. Oregon State Monographs Studies in Botany 3:1-31.
  • Hansen, H. P. 1941b. Paleoecology of a peat deposit in west central Oregon. American Journal of Botany 28:206-212.
  • Hansen, H. P. 1943. Paleoecology of two sand dune bogs on the southern Oregon coast. American Journal of Botany 30:335-340.
  • Hansen, H. P. 1944. Further pollen studies of a peat bog on the Pacific coast of Oregon and Washington. Bulletin of the Torrey Botanical Club 71:627-636.
  • Howarth, J. 1995. Gearhart Bog Preserve: Plant community mapping and background information. The Nature Conservancy, Oregon Field Office, Portland. 36 pp. plus appendices.
  • Kagan, J. S., J. A. Christy, M. P. Murray, and J. A. Titus. 2004. Classification of native vegetation of Oregon. January 2004. Oregon Natural Heritage Information Center, Portland. 52 pp.
  • Kunze, L. M. 1994. Preliminary classification of native, low elevation, freshwater wetland vegetation in western Washington. Washington State Department of Natural Resources, Natural Heritage Program. 120 pp.
  • Rigg, G. B. 1933. Notes on a sphagnum bog at Fort Bragg, California. Science 77:535-536.
  • Wade, L. K. 1965. Vegetation and history of the sphagnum bogs of the Tofino area, Vancouver Island. M.S. thesis, University of British Columbia, Vancouver. 125 pp.
  • Western Ecology Working Group of NatureServe. No date. International Ecological Classification Standard: International Vegetation Classification. Terrestrial Vegetation. NatureServe, Boulder, CO.