Black spruce / Field horsetail - Dwarf birch
	Picea mariana / Equisetum arvense – Betula nana
	n = 5
	I.A.3. Needleleaf Woodland
	Ecosystem:  Discharge Slope, Relict Drainageway

Black spruce (Picea mariana) / field horsetail (Equisetum arvense) – dwarf birch (Betula nana) is a new type.  Coastal black spruce communities are poorly documented in the literature.  The most similar community DeVelice, et. al. (1999) describe is a black spruce / lingonberry (Vaccinium vitis-idaea) (PICMAR / VACVIT) type on nearby Chugach National Forest.  Yarie (1983) describes a remotely similar black spruce / dwarf birch / cottongrass / sphagnum moss type for the Porcupine River drainage in interior Alaska.

Black spruce / Field horsetail - Dwarf birch is an uncommon plant community occupying a few groundwater discharge slopes at relict glacial lakebed fen edges near the coast.  Four of the sites visited cluster on the southern peninsula near Nikolaevesk, while the fifth (with much lower horsetail abundance) is located on the large isostatically rebounded marine terrace between the Kenai and Kasilof Rivers.  

Black spruce / Field horsetail – Dwarf birch forms an open to woodland canopy of medium-height black spruce with a moderately closed understory shrubland and abundant field horsetail.  Crowberry (Empetrum nigrum) is common, and cloudberry (Rubus chamaemorus) can be abundant.  The low shrubs, Labrador tea (Ledum palustre ssp. decumbens), and bog blueberry (Vaccinium uliginosum) are present in low abundance, as is bluejoint grass (Calamagrostis canadensis).  The shrubs, leatherleaf (Chamaedaphne calyculata) and lingonberry are also typically present.  

The organic mat is often thicker than one meter, and the water table is always within 20 cm of the surface.  pH was only slightly acid (6.3) at the one site where it was measured.  All five of the sites visited qualify as 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
DOROSHIN	1	1
NIKOLAI	1	1
STARICHKOF	1	1, 2B2, 3

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	16.8		FACW	FACW-, FACW
Shrubs
Betula nana	1.0	26.3		FAC	FAC, OBL
Empetrum nigrum	1.0	11.3		FAC	FACU, FACW
Ledum palustre ssp. decumbens	1.0	8.8		FACW	FACW
Vaccinium uliginosum	1.0	4.0		FAC	FACU+, FACW
Chamaedaphne calyculata	0.8	4.3		FAC	FAC
Low shrub
Vaccinium vitis-idaea	0.8	0.7		FAC	FAC
Dwarf shrub
Vaccinium oxycoccos	1.0	0.3		OBL	OBL
Herbs/Graminoid
Equisetum arvense	1.0	48.0		FAC*	FAC*, FACW-
Rubus chamaemorus	1.0	29.3		FACW	FACW
Calamagrostis canadensis	1.0	1.3		FAC	FAC, OBL
Moss	1.0	87.5
Lichen	1.0	0.1

 

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Introduction and Key to Plant Communities   Introduction and Key to Ecosystems     Kenai Hydric Soils    Map Unit Summary    Methods    Glossary

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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