moss / Tall cottongrass
|Sphagnum spp. - Eriophorum angustifolium|
|n = 8|
|III.A.3.k (III.A.3.a.) Subarctic Lowland Sedge-Moss Bog Meadow (Wet Sedge Meadow Tundra)|
|Ecosystem: Relict Lakebed / Drainageway, Kettle, Depression|
This is a well known and widely documented community in Alaska (Craighead, et. al., 1988; Holowaychuk and Smeck, 1979, Viereck, 1963, White, et. al., 1975 and Murray, 1974 in Viereck, et. al., 1992; Racine, 1976; Racine and Anderson, 1979; Boggs, 2000 and DeVelice, et. al., 1999). Viereck, et. al. (1992), describe the majority of tall cottongrass (Eriophorum angustifolium) dominated communities as interior Alaska tundra types, i.e. underlain by permafrost. However, tall cottongrass communities are common on the Kenai lowlands, where permafrost is absent and the climate is maritime.
Sphagnum moss (Sphagnum spp.) – tall cottongrass is widespread and somewhat common on well-developed peat in wetter areas of relict glacial lakebeds.
In these communities, sparse to open tall cottongrass plants push up through a thick sphagnum mat sometimes with open dwarf birch (Betula nana) cover. Two dwarf shrubs, bog rosemary (Andromeda polifolia) and bog cranberry (Vaccinium oxycoccos) are usually present in trace amounts.
The organic mat is often over 1.5 m thick and the water table is usually at or very near the surface. pH is extremely to strongly acid (5.1) at the four sites measured. All sites visited are 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.
Table 2. Summary of plant frequency and average cover for plants occurring in more than 50% of plots.
|Wetland Indicator Status|
|Betula nana||1.0||5.6||FAC||FAC, OBL|
|Empetrum nigrum||0.6||10.0||FAC||FACU, FACW
|Vaccinium uliginosum||0.6||7.2||FAC||FACU+, FACW|
|Ledum palustre ssp. decumbens||0.8||2.6||FACW||FACW|
|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 10:03