Name:
Artemisia arbuscula ssp. arbuscula Shrub Herbaceous Alliance
Reference:
Western Ecology Working Group of...
Description:
This widespread shrub herbaceous alliance is known from cold, dry areas of the Intermountain West, as well as in dry alpine and subalpine habitats of the Sierra Nevada. Perennial grasses are prominent with Artemisia arbuscula ssp. arbuscula dominating the open to moderately dense low-shrub layer. Stands typically occur on shallow, rocky, poorly drained soils on a variety of landforms; from flats and depressions to slopes, ridges or alpine fell-fields. Soils are usually shallow, rocky clays, often with an impenetrable layer at less than 60 cm depth. Poor drainage often leads to perched water tables in the spring, which may control the distribution of the vegetation in this alliance and explain its patchy distribution. The vegetation is characterized by a moderate to dense herbaceous layer dominated by perennial graminoids. Dominant to common grass species include Achnatherum thurberianum (= Stipa thurberiana), Festuca idahoensis, Leymus salinus ssp. salmonis, Pascopyrum smithii, Poa secunda, Pseudoroegneria spicata, and Elymus elymoides (in areas in poor condition). Agoseris glauca, Allium spp., Antennaria rosea, Balsamorhiza sagittata, Castilleja angustifolia, Phlox hoodii, and Phlox longifolia are common forbs species. Shrub associates include Artemisia tridentata ssp. wyomingensis, Artemisia tridentata ssp. vaseyana, Artemisia nova, Chrysothamnus spp., Ephedra viridis, Gutierrezia sarothrae, Juniperus occidentalis, Juniperus osteosperma, Purshia tridentata, and Tetradymia canescens. Diagnostic of this alliance is a moderate (>20% cover) perennial graminoid layer with an Artemisia arbuscula ssp. arbuscula-dominated low-shrub layer that has 10-40% cover. At least 40% of the total shrub cover is Artemisia arbuscula ssp. arbuscula.
Accession Code:
VB.CC.23895.ARTEMISIAARBUSC
Plot-observations of this Community Concept:
0
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