Barclay's willow / Tufted hairgrass – Bluejoint
Salix barclayi / Deschampsia caespitosa - Calamagrostis canadensis
n = 4
II.C.2.g. Open Low Willow Scrub
Ecosystem: Depression, Relict Lakebed

   

This uncommon Kenai Lowlands community is included within the Barclay's willow (Salix barclayi) – mixed herb community documented by others (DeVelice et.al., 1999; Boggs, 2000; Shephard, 1995).  Tufted hairgrass (Deschampsia caespitosa) cover is greater on Kenai Lowlands sites.

Three of the sites visited occur in depression-like features on the terraced moraines fronting the western slope of the Caribou hills.  The fourth is at the edge of a large isostatically rebounded marine terrace along Coho Loop Road, near Kasilof.  

Barclay's willow / tufted hairgrass - bluejoint communities are characterized by a low, patchy Barclay's willow thicket interspersed with bluejoint (Calamagrostis canadensis) and tufted hairgrass in nearly equal proportions.  These communities are diverse, with arctic blackberry (Rubus arcticusand dwarf birch (Betula nanapresent in trace amounts, and variegated sedge (Carex stylosa),  jacob’s ladder (Polemonium acutiflorumboreal sage (Artemisia arctica),  field horsetail (Equisetum arvensemountain hairgrass (Vahlodea atropurpurea), boreal yarrow (Achillea millefolium var. borealis) and felwort (Swertia perennis) usually present.  

Organic horizons are thin, although one of the three plots has a histic epipedon (33 cm thick).  The water table is generally near the surface, but at one site redoximorphic features were measured at 58 cm below the surface.  Three of the four 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
CHUNILNA 2

2B3

TRUULI1 1
1Proposed series, definitely hydric

 

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
Shrub
Salix1 barclayi   1.0 37.5 FAC FAC, FACW
Dwarf shrub
Betula nana 1.0 0.6 FAC FAC, OBL
Herbs/Graminoids
Deschampsia caespitosa2   1.0 47.5 FAC FAC, FACW+
Calamagrostis canadensis   1.0 40.5 FAC FAC, OBL
Rubus arcticus 1.0 0.6 FAC FAC
Carex stylosa 0.8 3.7 OBL OBL
Polemonium acutiflorum   0.8 0.4 FAC FAC
Artemisia arctica 0.8 0.4 na
Equisetum arvense 0.8 0.1 FAC* FAC*, FACW-
Achillea millefolium var. borealis  0.8 0.1 FACU UPL, FACU
Vahlodea atropurpurea 0.8 0.1 FACW* FAC+, FACW
Swertia perennis 0.8 0.1 FACW FAC+, FACW+
Moss 1.0 48.0
Lichen 0.8 0.1
1 Plant with known morphological adaptation for occurrence in wetlands (USACE, 1987)
Plant with known physiological adaptation for occurrence in wetlands (USACE, 1987)

 


 Introduction and Key to Plant Communities  

Introduction and Key to Ecosystems

    Kenai Hydric Soils    Map Unit Summary    Methods   Glossary


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 10:01