Name:
Pleuraphis jamesii - Sporobolus airoides Herbaceous Vegetation
Reference:
Western Ecology Working Group of...
Description:
This once-extensive grassland of the northern Chihuahuan Desert, Colorado Plateau and Great Basin has been described in New Mexico from White Sands Missile Range and the upper Rio Puerco watershed, as well as in north-central Arizona and southeastern Utah. It has, however, experienced significant declines throughout its range. It primarily occurs in swales within open valley bottoms and alluvial flats, although sandsheets and dunes also can support the association. Sites are on level to gentle slopes (<15%) at elevations between 1300-2075 m (4260-6800 feet). Soils are generally deep, with surface textures ranging from loamy sands, fine loams to silty clay loams and clays, derived from substrates that include lava flows, cinders, eolian sands, alluvium and relict Pleistocene river cobbles. The vegetation is characterized by a sparse to moderately dense perennial herbaceous layer that is dominated by <i>Pleuraphis jamesii (= Hilaria jamesii)</i> with <i>Sporobolus airoides</i> as a subdominant. Total vegetation cover in grazed sites generally does not exceed 20% but may be as high as 50% in protected areas. Occasionally, <i>Sporobolus airoides</i> may be codominant or dominant over <i>Pleuraphis jamesii</i>. This association usually has a sparse but diverse shrub layer that may include scattered <i>Atriplex canescens, Atriplex confertifolia, Atriplex obovata, </i><i>Coleogyne ramosissima, </i><i>Ephedra torreyana, Ericameria nauseosa, Gutierrezia sarothrae, Krascheninnikovia lanata, Opuntia imbricata, Opuntia macrorhiza, Opuntia phaeacantha, Sarcobatus vermiculatus</i>, and <i>Yucca angustissima</i>. The key graminoid species dominate the herbaceous layer and account for more than 80% of the total plant cover. Associated herbaceous species, such as <i>Achnatherum hymenoides, Bouteloua gracilis, Muhlenbergia porteri, Muhlenbergia pungens, Muhlenbergia torreyi, Pascopyrum smithii, Scleropogon brevifolius, Sphaeralcea coccinea</i>, and <i>Sporobolus cryptandrus</i>, may be present with low cover. Biological soil crusts may be extensive in undisturbed examples of this association.
Accession Code:
VB.CC.32278.CEGL001778
Plot-observations of this Community Concept:
0
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