Name:
Juncus balticus Seasonally Flooded Herbaceous Alliance
Reference:
Western Ecology Working Group of...
Description:
This alliance often occupies seasonally flooded swales and wet, low- to mid-elevation sites. Habitats are often alkaline. It is a wide-ranging alliance, occurring from the plains to montane regions, and has much variability. Elevations range from sea level in California to 3500 m in Colorado. Montane plant associations can occur on alluvial terraces, floodplains, overflow channels, seeps, meadows, and near springs. Sites are typically gently sloping (1-3%) on all aspects. An association was documented in northern California coastal salt marshes. Soils are mineral with dark surface horizons containing large amounts of well-decomposed organic matter. Soils are Mollisols, or rarely Entisols. Soil texture ranges from silt to sandy loam. Water tables are often at or near the soil surface in early summer but may drop below 50 cm by late August. Soil reaction ranges from neutral to mildly alkaline (pH 7.0-8.0). The graminoid layer is dense with up to 98% cover and dominated by Juncus balticus, a creeping, often sod-forming, rhizomatous perennial. Other graminoid cover is minor but can include Carex pellita (= Carex lanuginosa), Carex aquatilis, Carex canescens, Leymus cinereus, Deschampsia caespitosa, Hordeum jubatum, or Sporobolus airoides. Forb cover is typically minor and may include Achillea millefolium, Iris missouriensis, or Geum macrophyllum. The plant association from California is composed of Distichlis spicata, Carex lyngbyei, Carex obnupta, and Schoenoplectus robustus (= Scirpus robustus). Occasionally, a few tree or shrub seedlings are present, including Populus angustifolia, Dasiphora fruticosa ssp. floribunda (= Pentaphylloides floribunda), and Salix exigua. Salix exigua shrublands, Distichlis spicata marshes, or Carex spp. meadows occur in adjacent riparian areas. Abies lasiocarpa - Picea engelmannii, Pseudotsuga menziesii, and Populus tremuloides forests, Pinus edulis - Juniperus spp. woodlands, and Ericameria nauseosa (= Chrysothamnus nauseosus), Sarcobatus vermiculatus, and Artemisia tridentata shrublands occur on adjacent hillslopes. In low-disturbance areas, Juncus balticus plant associations appear to be a stable, climax community. However, in some areas, this association is considered to be grazing-induced. Juncus balticus is considered an increaser due to its low forage value and high tolerance to grazing. It usually increases in abundance on sites formerly dominated by Deschampsia caespitosa or Calamagrostis canadensis. Nearly pure stands of Juncus balticus indicate that the site may have been heavily grazed in the past. Juncus balticus is listed as a facultative wetland species.
Accession Code:
VB.CC.22823.JUNCUSBALTICUSS
Plot-observations of this Community Concept:
0
|
