Common (Translated Scientific) Name: Lodgepole Pine / Dwarf Bilberry Forest

Colloquial Name: No Data Available

Hierarchy Level:  Association

Type Concept: This association is found in the upper montane and subalpine zone of the Rocky Mountains from north-central Colorado to southern Alberta. It is more common near and east of the Continental Divide, but occurs in the Uinta Mountains of northern Utah and in Idaho. Elevations range from 2950-3120 m (9700-10,240 feet) in northern Colorado down to 950-1800 m (3100-5900 feet) in the northern Rocky Mountains. It typically occurs on cold, dry-mesic sites where cold air accumulates causing high diurnal temperature fluctuations often with frequent summer frosts and high daily maximum temperatures. Topography is flat to gently undulating or moderately sloping terrain typically occurring on valley bottoms, terraces, lower slopes, and benches with variable aspects, but also on steep canyon slopes and benches, plateau tops and adjacent upper slopes in the Uinta Mountains. Soils are typically well-drained, moderately deep, acidic, gravelly or non-gravelly sandy loam, loam, silt loam, silt or less frequently clay that are typically derived from a variety of noncalcareous parent materials. Ground cover is mostly litter, often with duff over 3 cm deep. The vegetation is characterized by a Pinus contorta-dominated tree canopy with Vaccinium cespitosum dominating or codominating the patchy to continuous dwarf-shrub layer. The tree canopy varies from moderately dense to nearly closed (40-90% cover) and is often composed solely of Pinus contorta. However, in some stands scattered Abies lasiocarpa, Larix occidentalis, Picea engelmannii, Pinus albicaulis, Populus tremuloides, or Pseudotsuga menziesii trees may be present, especially in the subcanopy. Some stands have tree saplings and scattered shrubs. Vaccinium cespitosum (indicator species) is usually dominates or codominates the dwarf-shrub layer. Other dwarf-shrubs may include low cover of Arctostaphylos uva-ursi, Paxistima myrsinites, Ribes spp., Linnaea borealis (on more mesic sites), or Juniperus communis and Vaccinium scoparium (drier sites). The herbaceous layer is sparse to moderately dense (to 30% cover) and is typically dominated or codominated by perennial graminoids such as Calamagrostis rubescens, Danthonia intermedia, Deschampsia cespitosa, Carex geyeri, Carex rossii, or Festuca spp. Forbs are generally have sparse cover but may be diverse. Mosses and lichens are common (5-20% cover) on some sites.

Diagnostic Characteristics: No Data Available

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: Many lower subalpine, spruce-fir and upper montane Douglas-fir forest and woodland stands include Pinus contorta trees in a mixed-conifer canopy. To clarify classification, only stands with tree canopies strongly dominated by Pinus contorta (usually >2/3 tree canopy) are considered to be Pinus contorta woodland and forest associations.

Abies lasiocarpa / Vaccinium caespitosum Habitat Type (Williams et al. 1990b) may include seral stands that would be classified as this association, which would significantly extend its range westward. Further research is needed to resolve this question. Steele et al. (1981) report this association occurring in the Little Rocky Mountains, but Roberts (1980) did not classify it in his study.

Similar NVC Types: No Data Available

note: No Data Available