|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.
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
Table 1. Frequency of soil series occurrence and hydric status at NRCS holes. Bold type indicates soils on the NRCS Alaska hydric soils list.
Table 2. Summary of plant frequency and average cover for plants occurring
in more than 50% of plots.
Table 2. Summary of plant frequency and average cover for plants occurring in more than 50% of plots.
|Wetland Indicator Status|
|Picea mariana||1.0||16.8||FACW||FACW-, FACW|
|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|
|Equisetum arvense||1.0||48.0||FAC*||FAC*, FACW-|
|Calamagrostis canadensis||1.0||1.3||FAC||FAC, OBL|
|Contact: Mike Gracz Kenai Watershed Forum PO Box 15301 Fritz Creek, AK 99603 907-235-2218||
Alaska Natural Heritage Program
and Natural Resource Institute
707 A Street, Suite 101
Anchorage, Alaska 99501
04 May 2007 09:53