Name:
Pinus ponderosa / Vaccinium caespitosum Woodland
Reference:
Western Ecology Working Group of...
Description:
This association is found in the montane zone of the central and northern Rocky Mountains from western Montana, Idaho and northeastern Washington. Elevations range from 700-1370 m (2300-4500 feet) extending to 1950 (6400 feet) east of the Continental Divide. Sites are relatively warm and moist, typically with cold nights, often occurring where cold air accumulates causing high diurnal temperature fluctuations, high daily maximum temperatures and frequent summer frosts. Topography is flat to gently undulating or moderately sloping terrain typically occurring on valley bottoms, terraces, lower slopes, and benches on all aspects. Soils are typically excessively well-drained, moderately deep, acidic, gravelly, sandy loam or loam, derived from a variety of noncalcareous parent materials, especially glacial till. Ground cover is mostly tree litter, often with duff over 4 cm deep. The vegetation is characterized by an open to moderately dense tree canopy that is dominated by <i>Pinus ponderosa</i>. In some stands scattered <i>Pseudotsuga menziesii, Larix occidentalis, Populus tremuloides, Picea engelmannii</i>, or <i>Pinus contorta</i> trees may be present. <i>Vaccinium caespitosum</i> and <i>Arctostaphylos uva-ursi</i> (indicator species) are common to dominant in the patchy to continuous dwarf-shrub layer. Other shrubs and dwarf-shrubs may include low cover of <i>Amelanchier alnifolia, Linnaea borealis</i> (on more mesic sites), <i>Mahonia repens, Paxistima myrsinites, Ribes</i> spp., <i>Rosa woodsii, Spiraea betulifolia</i>, or <i>Symphoricarpos albus</i>. The herbaceous layer is sparse to moderately dense (to 30% cover) and is typically dominated or codominated by perennial graminoids in the openings such as <i>Calamagrostis rubescens, Carex geyeri</i>, or <i>Festuca</i> spp. Forbs generally have sparse cover but may be diverse and include <i>Arnica cordifolia, Balsamorhiza sagittata, Fragaria virginiana, Heuchera cylindrica, Maianthemum racemosum, Tiarella trifoliata</i>, and <i>Thalictrum occidentale</i>.
Accession Code:
VB.CC.32144.CEGL005841
Plot-observations of this Community Concept:
0
|
