|Barclay's willow / Bluejoint - Field horsetail|
|Salix barclayi / Calamagrostis canadensis – Equisetum arvense|
|n = 39|
|II.C.2.g. Open Low Scrub - Willow|
|Ecosystem: Riparian, Discharge Slope|
The Barclay's willow / bluejoint - field horsetail community probably occurs in other parts of Alaska, though not at the abundance found on the Kenai Lowlands. It is therefore usually lumped with other types such as the Barclay's willow (Salix barclayi) / bluejoint (Calamagrostis canadensis) type (Ritchie, et.al., 1981; DeVelice, et. al., 1999; Boggs, 2000), and the Barclay's willow – mixed herb type (DeVelice et. al., 1999; Boggs, 2000; Shephard, 1995).
Barclay's willow / bluejoint – field horsetail (Equisetum arvense) is common along southern peninsula riparian corridors, and adjacent discharge slopes, but also occurs on groundwater discharge slopes above relict glacial lakebeds. It is similar to the Barclay's willow / bluejoint association, but with a significant field horsetail component, and more diversity.
In this community, an open patchy thicket of Barclay's willow (rarely other willows, such as undergreen (Salix commutata) and tealeaf willow (S. pulchra), replace Barclay's willow) is interspersed with dense bluejoint grass, and an open, uniform field horsetail understory. Jacob’s ladder (Polemonium acutiflorum), arctic blackberry (Rubus arcticus) and open water are present. The open water frequently occurs as groundwater discharge springs and seeps.
These palnts occupy a wide range of sites. Soils at about a third of the sites visited had at least a histic epipedon (organic layer greater than 20 cm thick), and three were histosols (>40 cm organic layer). Another third had shallow water tables, while another third are probably not jurisdictional wetlands. The pH at the two sites measured was strongly acid (5.5) and slightly acid (6.1).
Table 1. Frequency of soil series occurrence and hydric
status at NRCS holes. Bold type indicates soils on the NRCS Alaska hydric
|STARICHKOF||2||1, 2B2, 3|
|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|
|Salix1 barclayi||1.0||52.6||FAC||FAC, FACW
|Calamagrostis canadensis||1.0||63.2||FAC||FAC, OBL|
|Equisetum arvense||1.0||23.8||FAC*||FAC*, FACW-|
|Chamerion angustifolium||0.6||4.2||FACU||FACU, FAC|
|Trientalis europaea||0.6||0.3||FAC||FAC*, FAC
|Swertia perennis||0.5||0.6||FACW||FAC+, FACW+|
|1 Plant with known morphological 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 10:01