Name:
Pinus ponderosa / Purshia tridentata Woodland
Reference:
Western Ecology Working Group of...
Description:
This <i>Pinus ponderosa</i> woodland occurs in montane zones in the Rocky Mountains and in sheltered canyons and high plateaus in the Colorado Plateau, from Colorado to Montana west to Utah, Washington, Oregon, and California. Stands tend to occupy south-facing, moderate to somewhat steep slopes (10-49%) in the Rockies, whereas Colorado Plateau stands prefer northern and eastern slopes and benches. Elevations range from 2165 to 2760 m (7100-9040 feet). Soils are relatively deep, mesic, well-drained sandy loams or loamy sands derived from sandstone, granite, colluvium or alluvium. Ground cover of litter and duff is often significant (30-60%). This <i>Pinus ponderosa</i> woodland is strongly dominated by <i>Pinus ponderosa</i>, often in open stands (10-40% cover) 10 to 35 m tall. <i>Pseudotsuga menziesii, Juniperus scopulorum, Pinus edulis</i>, and <i>Populus tremuloides</i> are common associates. The shrub layer is characterized and dominated by <i>Purshia tridentata</i>, although cover may be as low as 1% in sparsely vegetated stands. Additional species include <i>Quercus gambelii</i> (<10% cover), <i>Arctostaphylos uva-ursi, Artemisia bigelovii, Artemisia tridentata, Mahonia repens, Ribes cereum</i>, and <i>Juniperus communis</i>. In the northern states, <i>Amelanchier alnifolia, Prunus virginiana</i>, or <i>Symphoricarpos albus</i> occur. The herbaceous layer is inversely proportional to shrub cover and is dominated by graminoids, especially <i>Muhlenbergia montana</i>. Additional graminoids include <i>Bouteloua gracilis, Carex geyeri, Carex rossii, Danthonia parryi, Poa fendleriana, Pseudoroegneria spicata, Hesperostipa comata, Leucopoa kingii</i>, and <i>Festuca idahoensis</i>. Forbs are present and often diverse but have low cover. Forb composition largely depends on geographic region but often includes <i>Achillea millefolium var. occidentalis (= Achillea lanulosa), Antennaria</i> spp., <i>Artemisia ludoviciana, Eriogonum racemosum, Penstemon virens</i>, and <i>Sedum lanceolatum</i>, among many others. Bare ground and needle duff can be prevalent in some stands.
Accession Code:
VB.CC.33184.CEGL000867
Plot-observations of this Community Concept:
0
|
