Invalid Unit Specified
CEGL003400 Alnus rubra / Oxalis (oregana, trilliifolia) Riparian Forest

The U.S. National
Vegetation Classification
Type Concept Sentence:
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Common (Translated Scientific) Name: Red Alder / (Redwood Sorrel, Threeleaf Woodsorrel) Riparian Forest
Colloquial Name:
Hierarchy Level: Association
Type Concept: This association occurs in the southern Cascade foothills of Washington, including Mount Rainier and on the Olympic Peninsula, on relatively well-drained soils at lower elevations on riparian terraces, streambanks or floodplains. The canopy is dominated by Alnus rubra. Picea sitchensis or Tsuga heterophylla are frequently in the overstory but with low cover. When present, the tall-shrub layer is dominated by Acer circinatum. Rubus spectabilis or Ribes bracteosum may be present but under 20% cover in aggregate. The understory is dominated by Oxalis oregana or Oxalis trilliifolia. Polystichum munitum can be codominant or dominant in the herb layer. Many other forbs and ferns, including Athyrium filix-femina, Luzula fastigiata, Luzula parviflora, Tiarella trifoliata, Circaea alpina, and Tolmiea menziesii, are frequently present to prominent. Grasses, such as Elymus glaucus and Elymus hirsutus, are present to codominant but never dominant or more abundant in aggregate than Oxalis spp.
Diagnostic Characteristics: No Data Available
Rationale for Nominal Species or Physiognomic Features:
Classification Comments: This association concept has been expanded to include subassociations with a Acer circinatum-dominated shrub layer.
Similar NVC Types:
Physiognomy and Structure: No Data Available
Floristics:
Dynamics: No Data Available
Environmental Description: No Data Available
Geographic Range:
Nations: US
States/Provinces: OR, WA
US Forest Service Ecoregions (1994/1995)
Domain Name:
Division Name:
Province Name: Pacific Lowland Mixed Forest Province
Province Code: 242    Occurrence Status: Confident or certain
Section Name: Willamette Valley and Puget Trough Section
Section Code: 242A     Occurrence Status: Confident or certain
US Forest Service Ecoregions (2007)
Domain Name:
Division Name:
Province Name: Pacific Lowland Mixed Forest Province
Province Code: 242    Occurrence Status: Confident or certain
Section Name: Puget Trough Section
Section Code: 242A     Occurrence Status: Confident or certain
Omernik Ecoregions:
Confidence Level: Low
Confidence Level Comments:
Grank: G4
Greasons:
Name:Database Code:Classification Code:
Class 1 Forest & Woodland C01 1
Subclass 1.B Temperate & Boreal Forest & Woodland S15 1.B
Formation 1.B.3 Temperate Flooded & Swamp Forest F026 1.B.3
Division 1.B.3.Ng Vancouverian Flooded & Swamp Forest D193 1.B.3.Ng
Macrogroup M035 Vancouverian Flooded & Swamp Forest M035 1.B.3.Ng.1
Group G851 North-Central Pacific Lowland Riparian Forest G851 1.B.3.Ng.1.d
Alliance A3745 Bigleaf Maple - Red Alder Riparian Forest A3745
Association CEGL003400 CEGL003400
Concept Lineage:
Predecessors:
Obsolete Names:
Obsolete Parents:
Synonomy: = Alnus rubra / Oxalis spp. association (Diaz and Mellen 1996)
= Alnus rubra/Oxalis (oregana, trilliifolia) Forest (Crawford et al. 2009)
Concept Author(s): Crawford et al. (2009)
Author of Description: Crawford et al. (2009)
Acknowledgements:
Version Date: 17Jan2016
References:
  • Crawford, R. C., C. B. Chappell, C. C. Thompson, and F. J. Rocchio. 2009. Vegetation classification of Mount Rainier, North Cascades, and Olympic national parks. Plant association descriptions and identification keys: Appendices A-G. Natural Resource Technical Report NPS/NCCN/NRTR--2009/D-586. National Park Service, Fort Collins, CO. 586 pp.
  • Diaz, N. M., and T. K. Mellen. 1996. Riparian ecological types, Gifford Pinchot and Mt. Hood national forests, and Columbia River Gorge National Scenic Area. Technical Report R6-NR-TP-10-96. USDA Forest Service, Pacific Northwest Region, Portland, OR. 203 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.
  • Western Ecology Working Group of NatureServe. No date. International Ecological Classification Standard: International Vegetation Classification. Terrestrial Vegetation. NatureServe, Boulder, CO.
  • WNHP [Washington Natural Heritage Program]. 2018. Unpublished data files. Washington Natural Heritage Program, Department of Natural Resources, Olympia, WA.