Wetland Classification and Mapping of Seward, Alaska     Map Unit Descriptions   Ecosystem: Tidal   Map Component: T7   Seward Area Extent: 3 wetland polygon; 27.4 acres

An extensive, wet T7 wetland at the southern end of the Spruce Creek alluvial fan.

Wetland Indicators Type: Tidal Average depth to water table: Varies with tidal stage Organic layer thickness: o cm at the single site measured Average depth to redoximorphic features: n/a Common Soils: Oxyaquic Cryofluvents at the single site visited Common Plant communities: Beachrye (Leymus mollis ssp. mollis)

 

T7 wetlands are dominated by Beachrye (Leymus mollis ssp. mollis).  They are found on coastal storm berms and higher riverbank levees.  Vince and Snow (1984) describe 'Riverbank Levees' dominated by other grasses, and that "Still higher levees featured [Beachrye] and large forbs..."  Their lower elevation riverbank levees flood an average of 1 time per summer; probably higher T7 beachrye berms or levees flood only when storms correspond with the highest spring tides.  An unusual extensive wet T7 stand occupies the very southern corner of the Spruce Creek alluvial fan.

 

This map component is composed of tall, dense beachrye usually over a well drained sandy and gravelly soil.  While the dominant vegetation will always meet the plant criteria for a wetland, soils and hydrology criteria may not be present.