|Tufted bulrush – Sweetgale|
|Trichophorum caespitosum - Myrica gale|
|n = 31|
|II.C.2.j. Sweetgale Graminoid Bog|
|Ecosystem: Relict Lakebed / Drainageway, Kettle|
On the Copper River Delta some sweetgale (Myrica gale) types are documented, but tufted bulrush (Trichophorum caespitosum) is absent (Boggs, 2000). On Chugach National Forest a tufted bulrush type is described (TRICAE) that has sweetgale in only one of twelve plots (DeVelice, et. al., 1999). On the Yakutat forelands, about half the tufted bulrush communities visited contained a sweetgale component (Shephard, 1995). A sweetgale - tufted bulrush type has been documented by Hogan and Tande (1983) and Tande (1983) working around the Anchorage area. Viereck (1970) describes a similarly named type for the Wood River Lakes. Unlike at those locales, where sweetgale is dominant and robust, many tufted bulrush – sweetgale communities on the Kenai Lowlands have a dominant bulrush component and scattered, low-stature sweetgale.
Tufted bulrush – sweetgale is very common on relict glacial lakebeds and drainageways on the Kenai lowlands. It occupies an intermediate zone between the wettest pools (or on flarks) and the higher, low relief peat ridges between them (strangs). Tufted bulrush prefers the wetter areas, and sweetgale a little drier, so this type represents a transitional zone; but one that is common.
At a typical site occupied by this community, bulrush dominates, with scattered low-stature sweetgale. Dwarf birch (Betula nana) and open water pools are present. Bog rosemary (Andromeda polifolia), tall cottongrass (Eriophorum angustifolium) and bog cranberry (Vaccinium oxycoccos) are usually present.
layers are thick, usually over one meter (40”), and often greater than 1.5
meters (60”). The water table is at or very close to the surface.
pH ranged from strongly to moderately acid (5.3-6.0) at the three sites
where it was measured. All sites
examined qualified 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.
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||7.4||FAC||FAC, OBL|
|Ledum palustre ssp. decumbens||0.5||2.1||FACW||FACW|
|Dasiphora floribunda||0.7||9.3||FAC||FAC-, FACW|
|Empetrum nigrum||0.7||3.5||FAC||FACU, FACW|
|Swertia perennis||0.5||0.4||FACW||FAC+, FACW+|
|1,2 Plant with known morphological and physiological adaptation for occurrence in wetlands (USACE, 1987)|
|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 10:04