Lutz spruce / Dwarf birchField horsetail
Picea X lutzii /Betula nana – Equisetum arvense   
n = 8
II.A.3. Dwarf tree scrub woodland
Ecosystem: Relict Lakebed, Depression, Discharge Slope


This community has not been documented in Alaska.  Lutz spruce communities are poorly represented in the literature, and no white spruce peatland types are described.  The closest types, peatland black spruce (Picea mariana) communities, do not include field horsetail (Equisetum arvense).  The closest related community may be Yarie’s (1983) black spruce / dwarf birch / sedge community for the Porcupine River drainage of interior Alaska.

Lutz spruce / dwarf birch - field horsetail is very common in and around the 15,000 acre fen complex east of Anchor Point (“Daryl’s Fen”).  Another plot was sampled on a terrace above the Anchor River.  

Stunted or medium height Lutz spruce (Picea X lutzii) dots a low thicket of dwarf birch (Betula nana) with three ericaceous shrubs, crowberry (Empetrum nigrum), Labrador tea (Ledum palustre ssp. decumbens), and bog blueberry (Vaccinium uliginosum). Field horsetail and cloudberry (Rubus chamaemorus) cover is uniformly scattered, to continuous.  Two dwarf shrubs, lingonberry (Vaccinium vitis-idaea) and lowbush cranberry (Vaccinium oxycoccos), are present and occasionally so is bluejoint grass (Calamagrostis canadensis).

The organic horizon is typically greater than 1.5 meters thick; at one locale, north of the large fen complex east of Anchor Poitn (Daryl’s Fen), it is less than the 40 cm needed to qualify as an organic soil (meeting the soils criterion for a jurisdictional wetland).  The water table is almost always within 20 cm of the surface.  All the sites visited qualify as jurisdictional wetlands.

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

  Soil Series n

Hydric Criteria Number

STARICHKOF 3 1, 2B2, 3
1Proposed series, definitely hydric

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

        Wetland Indicator Status



 Average Cover

  Alaska National
Shrubs/Stunted tree
stunted Picea X lutzii 1.0 12.9 np
Betula nana 1.0 42.5 FAC FAC, OBL
Empetrum nigrum 1.0 24.3 FAC FACU, FACW
Ledum palustre ssp. decumbens   1.0 15.3 FACW FACW
Vaccinium uliginosum 1.0 14.4 FAC FACU+, FACW
Vaccinium vitis-idaea 1.0 2.3 FAC FAC
Dwarf shrubs
Vaccinium oxycoccos 0.9 0.6 OBL OBL
Andromeda polifolia 0.6 0.5 OBL OBL
Salix1 fuscescens   0.8 1.9 FACW FACW
Rubus chamaemorus 1.0 23.0 FACW FACW
Equisetum arvense 0.9 24.3 FAC* FAC*, FACW-
Calamagrostis canadensis   0.8 3.5 FAC FAC, OBL
Moss 0.9 95.0
Open water 0.8 1.4
np- not present on the wetland indicator status list
1 Plant with known morphological 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  996033
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 09:51