Print Report

CEGL002629 Alnus incana / Lysichiton americanus Wet Shrubland

Type Concept Sentence: No Data Available

Common (Translated Scientific) Name: Gray Alder / Yellow Skunk-cabbage Wet Shrubland

Colloquial Name: No Data Available

Hierarchy Level:  Association

Type Concept: This association is found between 573 to 1098 m (1880-3600 feet) elevation in maritime climate-influenced areas along both the western and eastern slopes of the Cascades in Washington and Oregon, and in the southern end of the Canadian Rockies of northeastern Washington and far northern Idaho. It is a wet association almost totally restricted to low-gradient sites, predominantly found in moderate width valleys. It is most commonly found in wetlands along pond and lake margins, on organic loam and muck soils with up to 50% of the surface flooded during the spring. Alnus incana (8-10 m tall) dominates this association with 30-70% cover, although Cornus sericea and Spiraea douglasii commonly occur with moderate constancy and cover. Thuja plicata often occurs, but with low cover, and its presence may indicate a potential successional pathway for the stand. The only forb with high cover is Lysichiton americanus, about 10-40% cover. Athyrium filix-femina, Circaea alpina, Equisetum spp., Viola spp., and other forbs or ferns with low to moderate cover may form a ground layer. The only graminoids with high constancy (but low cover) are Glyceria striata and Phalaris arundinacea. Moderate ground cover of moss, including Sphagnum spp., is sometimes observed.

Diagnostic Characteristics: No Data Available

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: This association is defined as a PNV vegetation type. If it were renamed as a dominance type the species would include Alnus incana (ALIN) and COST. This association is described from a total of 15 plots and 5 qualitative observations: 8 plots in eastern Washington (Kovalchik 2001); 5 plots on the west and central portions of the Cascades in southern Washington and northern Oregon (which may have different species composition and represent a different phase of this association) (Murray 2000); and from 2 plots and 5 stand observations in the northern Idaho Panhandle (IDCDC 2002). It is distinguished from ~Alnus incana / Athyrium filix-femina Wet Shrubland (CEGL002628)$$, and from other Alnus incana types by having conspicuous Lysichiton americanus present (at least 5% cover).

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

Floristics: Alnus incana (8-10 m tall) dominates this association with 30-70% cover, although Cornus sericea and Spiraea douglasii commonly occur with moderate constancy and cover. Thuja plicata often occurs, but with low cover, and its presence may indicate a potential successional pathway for the stand. The only forb with high cover is Lysichiton americanus, about 10-40% cover. Athyrium filix-femina, Circaea alpina, Equisetum spp., Viola spp., and other forbs or ferns with low to moderate cover may form a ground layer. The only graminoids with high constancy (but low cover) are Glyceria striata and Phalaris arundinacea. Moderate ground cover of moss, including Sphagnum spp., is sometimes observed.

Dynamics:  Most stands of Alnus incana are minimally impacted by logging, livestock, and human activities due to their dense, often wet environments, as well as their high productivity and resiliency (Kovalchik 2001). However, wildlife browsing heavily impacts the survival of Alnus incana seedlings. Established plants can resprout from root crowns or stumps when their stems are damaged by beaver, floods, fire or other disturbance, with the exception of fire that is severe enough to kill the root crown. Fire is infrequent in the high-moisture, cool sites that support this association, but stands may be impacted by adjacent upland fires in conifers. Alnus incana has poor to fair palatability for livestock and ungulates, but seedlings may be heavily browsed in late summer by livestock when herbaceous forage is minimal. Although seedling establishment can occur on organic soil, seedling establishment is best on exposed mineral soil (Kovalchik 2001). Numerous seeds are dispersed by wind and water, which causes rapid colonization of mineral soil exposed by flood or fire. These disturbances are relatively uncommon in wetlands supporting this association. The overuse of Alnus incana for several consecutive years can lead to elimination of young age classes and decrease overall plant vigor. This association is less intensively grazed because surface water and wet organic soils limit livestock access (Kovalchik 2001). However, any alteration of the saturated wetland conditions (e.g., compaction and drainage of organic soils) necessary to support this association may lead to its rapid loss.
Environmental Description:  This association is found between 573 to 1098 m (1880-3600 feet) elevation in maritime climate-influenced areas along both the western and eastern slopes of the Cascades in Washington and Oregon, and in the southern end of the Canadian Rockies of northeastern Washington and far northern Idaho. It is a wet association almost totally restricted to low-gradient sites, predominantly found in moderate width valleys. It is most commonly found in wetlands along pond and lake margins, on organic loam and muck soils with up to 50% of the surface flooded during the spring.
Geographic Range: This association is found in maritime climate-influenced areas of the southern Canadian Rockies in Washington and Idaho, and from the Cascade Range in Washington and Oregon. There are no known occurrences in British Columbia or Montana; however, environmental conditions in these adjacent areas are likely to support this plant community.

Nations: CA?,US

States/Provinces:  BC?, ID, MT?, WA


Confidence Level: Moderate

Confidence Level Comments: No Data Available
Grank: G3

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.4 Temperate to Polar Freshwater Marsh, Wet Meadow & Shrubland Formation F013 2.C.4
Division 2.C.4.Nb Western North American Temperate Freshwater Marsh, Wet Meadow & Shrubland Division D031 2.C.4.Nb
Macrogroup 2.C.4.Nb.5 Sitka Alder - Booth''s Willow / Northwest Territory Sedge Montane Marsh, Wet Meadow & Shrubland Macrogroup M893 2.C.4.Nb.5
Group 2.C.4.Nb.5.d Willow species - Alder species - Water Birch Riparian & Seep Shrubland Group G527 2.C.4.Nb.5.d
Alliance A3771 Gray Alder - Green Alder Wet Shrubland Alliance A3771 2.C.4.Nb.5.d
Association CEGL002629 Gray Alder / Yellow Skunk-cabbage Wet Shrubland CEGL002629 2.C.4.Nb.5.d
Concept Lineage: No Data Available

Predecessors: No Data Available

Obsolete Names: No Data Available

Obsolete Parents: No Data Available
Synonomy: = Alnus incana / (Lysichiton americanum) (Murray 2000)
= Alnus incana / Lysichiton americanum Association (Kovalchik 1993) [(p.116)]
= Alnus incana / Lysichiton americanus Association (Christy 2004)
Concept Author(s): C. Murphy

Author of Description: C. Murphy

Acknowledgements: No Data Available

Version Date: 10-18-02
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