|Black Spruce / Crowberry - Lingonberry|
|Picea mariana / Empetrum nigrum - Vaccinium vitis-idaea|
|n = 36|
|I.A.2.f /1.k. Open Black Spruce Forest / Closed Black Spruce Forest|
|Ecosystem: Discharge Slope|
This type has been described for Alaska. DeVelice, et. al. (1999) list a black spruce (Picea mariana) / lingonberry (Vaccinium vitis-idaea) (PICMAR / VACVIT) type on Chugach National Forest, that is nearly identical to this Kenai lowlands type.
Viereck et. al. (1992), list nominally similar types under both an open and closed canopy black spruce forest, although neither type resembles the Kenai lowlands community. The closed canopy type, Black spruce / Labrador tea / Lingonberry / Cladonia, is a dryland type, found also on the lowlands, but different from this wetland community. The open forest Black spruce / Blueberry community is more broadly defined.
Black spruce / crowberry (Empetrum nigrum) - lingonberry communities occupy two distinct ecotypes: An upland “black spruce lichen woodland” and a peatland type, described here. The line between the two ecotypes is blurry, so some of the sites visited for this analysis might fit into the lichen woodland as well. This plant community occurs primarily on foot and toeslopes of kames. Kames are frequently island landforms in a sea of peatlands. Foot and toeslopes, the transition zone from peatland to upland, are frequently narrow north of Clam Gulch. On this position, an elevated water table is supported by groundwater discharge or dense till.
An open black spruce canopy shades an often dense low shrub thicket. Crowberry and lingonberry co-dominate almost equally, while dwarf birch (Betula nana) and bog blueberry (Vaccinium uliginosumare usually present in low abundance. Cloudberry (Rubus chamaemorus) is typically present, and field horsetail (Equisetum arvense) may be common. More horsetail and crowberry typically indicates wetter conditions.
The organic mat
varies from being over 1.5 m thick to only 6 cm thick at one site.
The water table may be near the surface, or deeper than 1.5 m.
This type doesn’t always indicate the presence of a wetland: Half of the sites measured
meet the criteria for classification 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.
|STARICHKOF||2||1, 2B3, 3|
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||19.2||FACW||FACW-, FACW|
|Empetrum nigrum||1.0||9.5||FAC||FACU, FACW
|Vaccinium uliginosum||0.9||3.9||FAC||FACU+, FACW
|Ledum palustre ssp. decumbens||0.7||1.6||FACW||FACW|
|Betula nana||0.6||4.5||FAC||FAC, OBL
|Equisetum sylvaticum||0.8||4.4||FACU||FACU, FACW|
|Calamagrostis canadensis||0.6||1.8||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