Wetland Classification and Mapping of Seward, Alaska

An extension of wetland classification and mapping of the Kenai Lowland


Map Unit Descriptions


Ecosystem: Depression


Map Units: D32, D23


Seward Area Extent:

D32: 2 wetland polygons; 5.2 acres.

D23: 2 wetland polygons; 2.1 acres.


A mixed D32 Depression dominated by dwarf birch, crowberry, bog blueberry and fewflower sedge, near the Snow River.  A few low spots dominated by tufted bulrush and tall cottongrass have a shallower water table.

Wetland Indicators

Type: Peat, or mineral

Average depth to water table: 20 cm

Organic layer thickness: 150+ cm, at the single peatland, and 20 cm at the single mineral soil wetland measured

Average depth to redoximorphic features: n/a if peat, 8 cm in the single mineral soil wetland measured

Common Soils: Typic Cryohemists, Typic Cryaquods

Common Plant communities:

D2 component:

Tufted bulrush - dwarf birch (Tricophorum caespitosum - Betula nana)

Sphagnum - tall cottongrass (Sphagnum spp. - Eriophorum angustifolium)

D3 Component:

Crowberry - Labrador tea (Empetrum nigrum - Ledum palustre spp. decumbens)

Sphagnum - Ericad (Sphagnum spp. - Ericaceous shrub)

Fewflower sedge - Dwarf birch (Carex pauciflora - Betula nana)


HGM: Terrene Basin Isolated.


These are uncommon peatlands with mixed sedge (D2) and shrub-dominated (D3) components in bedrock depressions not hydrologically connected at or very near the surface with other wetlands.  Sedge-dominated components have a water table at or near the surface for most of the growing season, and shrubby components (D3) have a deeper water table.  These uncommon wetlands occur either on the bedrock ledges above the Snow River Valley, or on the bedrock knob north of Bear Lake.


Do I Need a Permit?

 Introduction and Key to Plant Communities  

Introduction and Key to Ecosystems

   Seward Soils   Map Unit Summary    Methods    Glossary



Contact: Mike Gracz
Kenai Watershed Forum 
Homer Field Office
Old Town Professional Center
3430 Main Street Suite B1
Homer, AK  99603

12 February 2007 15:11