Black spruce / Labrador tea
Picea mariana / Ledum palustre ssp. decumbens
n = 46
I.A.2.f. Black Spruce Open Needleleaf Forest
Ecosystem: Relict Lakebed / Drainageway, Kettle, Discharge Slope, Depression

This is a common Alaskan vegetation type however, it is not reported by either DeVelice et. al. (1999), on Chugach National Forest or Boggs (2000) on the Copper River Delta.  Nominally, it is closest to the Black spruce (Picea mariana) / Labrador tea (Ledum palustre) / feathermoss (Hylocomium splendens) type described for interior Alaska floodplains (Viereck, 1989).  However, on the Kenai lowlands, it occupies a significantly different landscape position and typically has sphagnum moss as the dominant ground cover.

On the Kenai lowlands, Black spruce / Labrador tea (Ledum palustre ssp. decumbens) is most frequent on areas of deeper peat on relict glacial lakebed and kettle fringes.  Two sites are located on kame-like features with shallow organic horizons.  It occurs most commonly on north of Ninilchick, where black spruce is more common, but a few locales in the south also support this community.  

The black spruce canopy is generally open, with an open, low Labrador tea shrub layer.  Dwarf birch (Betula nana) is common, bog blueberry (Vaccinium uliginosum) is often present, and crowberry (Empetrum nigrum) may be abundant.  Cloudberry (Rubus chamaemorus) is typically the only abundant forb; but bluejoint grass (Calamagrostis canadensis) occurs in about half the plots, usually in trace amounts. 

A thick organic layer usually supports a water table less than 20 cm from the surface.  The pH can vary widely, from very strongly acid to neutral.  Only one site of the 46 visited, located on an unusual kame-like feature near Kenai, did not meet the soil criteria for a jurisdictional wetland.

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 16 1, 2B2, 3
NIKOLAI 3 1
KALIFONSKY 2 2B3
FORELAND 2 2B3
CLAM GULCH 1 2B3
COAL CREEK 1 2B3
DOROSHIN 1 1
SALAMATOF 1 1, 3
SLIKOK 1 2B3, 3
TLIKAKILA1 1  
TRUULI1 1 1
1Proposed series, definitely hydic.

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

        Wetland Indicator Status

  Plant

f

 Average Cover

  Alaska National
Tree
Picea mariana   1.0 18.1 FACW FACW-, FACW
Shrubs
Empetrum nigrum 1.0 24.2 FAC FACU, FACW
Ledum palustre ssp. decumbens   1.0 20.5 FACW FACW
Betula nana 1.0 12.6 FAC FAC, OBL
Vaccinium uliginosum 0.9 5.3 FAC FACU+, FACW
Vaccinium vitis-idaea 0.8 2.5 FAC FAC
Dwarf shrubs
Vaccinium oxycoccos 0.8 0.6 OBL OBL
Andromeda polifolia 0.7 0.6 OBL OBL
Herb
Rubus chamaemorus 1.0 21.3 FACW FACW
Moss 0.8 90.5
Lichen 0.8 1.0      

 


 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
907-235-2218
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 09:53