Name:
Pseudoroegneria spicata - Poa secunda Herbaceous Vegetation
Reference:
Western Ecology Working Group of...
Description:
This association has been described from lower montane to subalpine elevations in British Columbia, Washington, Oregon, Idaho, Utah, Colorado, Wyoming, and Montana. Stands of this association occupy loamy, rocky, often shallow soils on slopes and ridges, generally around the edges of basins and in the foothills of the mountains. Sites usually are ridges and slopes, sometimes alluvial fans, scree slopes, sloped rocky cliff faces, and bedrock outcrops of any aspect, although southerly and westerly aspects are most common in the Northwest. Throughout its geographic range this is a bunch grassland with minor cover of forbs and, often, sparse shrubs. <i>Pseudoroegneria spicata</i> dominates or codominates the vegetation; <i>Poa secunda</i> and <i>Koeleria macrantha</i> usually are present in substantial amounts, and <i>Festuca idahoensis</i> is absent or present in very small amounts. The common shrubs are <i>Ericameria nauseosa (= Chrysothamnus nauseosus), Chrysothamnus viscidiflorus</i>, and <i>Artemisia tridentata</i> (subspecies unknown). Associated forbs are highly variable, given the broad geographic and elevational range. This association was at one time common throughout its wide geographic range, but much of it in Washington and Oregon has been converted to agricultural fields. In many of the remaining stands, the cover of <i>Pseudoroegneria spicata</i> has decreased and the cover of <i>Hesperostipa comata (= Stipa comata)</i> and shrubs have increased, and exotics (especially <i>Bromus tectorum, Tragopogon</i> spp., and <i>Alyssum</i> spp.) have become common members of the vegetation; these changes are attributed in large part to livestock grazing.
Accession Code:
VB.CC.32722.CEGL001677
Plot-observations of this Community Concept:
0
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