Bog blueberry – Dwarf birch – Tufted hairgrass
Vaccinium uliginosum – Betula nana – Deschampsia caespitosa   
 n = 5
II.C.2.e. Ericaceous Shrub Bog
Ecosystem: Relict Lakebed

This type has not been previously documented in Alaska.  A similar crowberry (Empetrum nigrum) community with bog blueberry (Vaccinium uliginosum) is frequently described (Hultén, 1960, in Viereck, et. al., 1992; Boggs, 2000.  DeVelice, et. al., (1999) and Shephard (1995) describe a bog blueberry - crowberry type which includes a significant tufted hairgrass (Deschampsia caespitosa) component.  However, unlike on the Kenai, none of these types has any dwarf birch (Betula nana) present.  Many workers have described closely related and variable types lumped under the shrub birch (Betula glandulosa,  which has been tentatively lumped with B. nana) - bog blueberry – sedge / sphagnum type (Brock and Burke, 1980, Hanson, 1953; Viereck, 1970; Racine, 1978a&b; Hogan and Tande, 1983) in The Alaska Vegetation Classification (Viereck, et. al., 1992). 

Bog blueberry – dwarf birch – tufted hairgrass is a diverse plant community generally found on relict glacial lake beds on the southern peninsula.   A few areas at the margin of the large fen complex east of Anchor Point are occupied by this type.

Bog blueberry cover is about 50%, with about half as much dwarf birchCrowberry is present at woodland densities, as is tufted hairgrass (at one site replaced by Bering’s tufted hairgrass, (Deschampsia beringensis)).  Manyflower sedge (Carex pluriflora), field horsetail (Equisetum arvense), bog cranberry (Vaccinium oxycoccos), and bog rosemary (Andromeda polifolia) are often present.  

The organic mat is greater than 1.5 m (60”) thick, and the water table is not far below the surface (0-15 cm). One unusual site is located on the large lakebed fen east of Anchor Point, with a thinner peat layer (58 cm, 23”), and deeper water table (51 cm, 20”).  The pH at the one site measured was neutral, at 6.5.  All five sites are jurisdictional wetlands.

Table 1. Frequency of soil series occurrence and hydric status at NRCS holes.  Bold type indicates soils on the NRCS Alaska hydric soils list.

   Soil Series n Hydric Criteria Number
STARICHKOF 4 1, 2B2, 3


Table 2.  Summary of plant frequency and average cover for plants occurring in more than 50% of plots.

        Wetland Indicator Status


f  Average Cover   Alaska National
Vaccinium uliginosum 1.0 46.0 FAC FACU+, FACW
Betula nana 1.0 22.0 FAC FAC, OBL
Empetrum nigrum 1.0 9.5 FAC FACU, FACW
Dwarf shrubs
Vaccinium oxycoccos 0.8 0.8 OBL OBL
Andromeda polifolia 0.8 0.5 OBL OBL
Deschampsia caespitosa2   0.8 7.8 FAC FAC, FACW+
Carex pauciflora   0.8 4.0 OBL OBL
Equisetum arvense 0.8 2.4 FAC* FAC*, FACW-
Rubus chamaemorus 0.6 14.2 FACW FACW
Trichophorum caespitosum   0.6 9.0 OBL OBL
Swertia perennis 0.6 4.8 FACW FAC+, FACW+
Polemonium acutiflorum   0.6 1.0 FAC FAC
Sanguisorba canadensis 0.6 0.7 FACW FACW
Calamagrostis canadensis   0.6 0.5 FAC FAC, OBL
Moss 0.8 76.3      
2Plant with known physiological adaptation for occurrence in wetlands (USACE, 1987)


 Introduction and Key to Plant Communities  

Introduction and Key to Ecosystems

    Kenai Hydric Soils    Map Unit Summary    Methods   Glossary

Contact: Mike Gracz
Kenai Watershed Forum 
PO Box 15301
Fritz Creek, AK  99603
The Alaska Natural Heritage Program
Environment and Natural Resource Institute
University of Alaska, Anchorage
707 A Street, Suite 101
Anchorage, Alaska  99501

04 May 2007 10:05