Name:
Pinus discolor Woodland Alliance
Reference:
Western Ecology Working Group of...
Description:
This woodland alliance occurs in mountains below the Mogollon Rim in southeastern Arizona, southwestern New Mexico and northern Mexico. Sites are typically on moderate to very steep, rocky slopes of foothills and mountains and on ridgetops, but may occur in cool microsites of canyons, washes and along drainages. Aspect is variable, but stands are typically on the less xeric northern slopes. Soils are shallow, coarse-textured and rocky. Woodlands included in this alliance are characterized by a moderately sparse upper tree canopy, typically 5-10 m tall, often with a sparse to moderately dense subcanopy. The upper canopy is dominated by the conifer Pinus discolor. Scattered Pinus ponderosa or Pinus leiophylla may be present in higher elevation stands. The subcanopy is a mixture of several different species of Juniperus and Quercus trees. The shrub layer is sparse to moderately dense depending on the density of the tree canopy. It can be a relatively rich mixture of deciduous or evergreen broad-leaved, microphyllous and rosette-leaved shrubs, 0.5-5 m tall. The layer includes xeric shrubs such as Agave palmeri, Arctostaphylos spp., Cercocarpus montanus, Dasylirion wheeleri, Garrya wrightii, Nolina microcarpa, Opuntia spp., Ptelea trifoliata, Quercus spp., Rhus trilobata, Yucca spp. The herbaceous layer is sparse to moderately dense (1-40% cover). Perennial graminoids are the most abundant species, particularly Muhlenbergia emersleyi or Piptochaetium fimbriatum. Other common graminoids include species of Aristida, Bouteloua, Cyperus, Eragrostis, Koeleria, Muhlenbergia, and Schizachyrium. Forbs are typically sparse. Some of the more common forbs include species of Artemisia, Cheilanthes, Chenopodium, Ageratina, Hedeoma hyssopifolia, Geranium, Senecio, Thalictrum, and Viguiera. Diagnostic of this woodland alliance is the dominance of Pinus discolor in the tree canopy.
Accession Code:
VB.CC.19157.PINUSDISCOLORWO
Plot-observations of this Community Concept:
0
|
