Name:
Pinus edulis - Juniperus osteosperma Colorado Plateau Shrubby Open Woodland Alliance
Reference:
NatureServe Biotics 2019
Description:
This open woodland and scrub alliance is characteristic of exposed rocky mesatops and canyon slopes and rims on the Colorado Plateau, but extends upslope into foothills and on xeric sites. The vegetation is sparse to moderately dense (10-80% total vegetation cover) and is dominated by dwarfed (usually <3 m tall) <i>Pinus edulis</i> and/or <i>Juniperus osteosperma</i> trees that form extensive tall shrublands or scrublands in the canyon country of the Colorado Plateau region. Both tree species are present with 3-25% cover. The understory is lacking or characterized by an open to moderately dense layer of shrubs (>10% cover) or, if less, then exceeding cover of grasses. Shrubs, if present, often include <i>Artemisia bigelovii, Atriplex canescens, Cercocarpus intricatus, Cercocarpus montanus, Chrysothamnus viscidiflorus, Coleogyne ramosissima, Ephedra torreyana, Ephedra viridis, Fendlera rupicola, Glossopetalon spinescens var. aridum, Petradoria pumila, Purshia stansburiana, Quercus havardii var. tuckeri</i>, or <i>Quercus turbinella</i>. Herbaceous layers are typically sparse and composed of xeric grasses and forbs. <i>Opuntia fragilis</i> or cushion plants such as <i>Arenaria eastwoodiae</i> and <i>Paronychia sessiliflora</i> may characterize the understory and exceed shrub cover. Sites are variable but generally xeric. Stands occur on dry canyon rims, ridges, hills, benches, hogbacks, mesas, elevated plains and occasionally in intermittent drainages. Elevations generally range from 1400 to 2165 m (4600-7100 feet), but may extend up to 2480 m (8135 feet). Stands typically occur on gentle to moderately steep slopes on all aspects, but range from flat to steep slopes (0-30%). The soils are variable but generally shallow, poorly developed and skeletal, ranging from well-drained clay loam or sandy clay to rapidly drain loamy sand. The unvegetated ground surface is typically composed of litter, bedrock, and bare soil. Because this is a relatively xeric woodland, bare soil and rocks may cover up to 70% of the unvegetated surface, although biological soil crusts provide up to 40% cover.
Accession Code:
urn:lsid:vegbank.org:commConcept:38793-{5E6DB444-5753-44EC-9CEE-963FD7C6E482}
Plot-observations of this Community Concept:
0
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