Common (Translated Scientific) Name: Lodgepole Pine / Thinleaf Huckleberry / Common Beargrass Forest

Colloquial Name: No Data Available

Hierarchy Level:  Association

Type Concept: This large-patch to matrix type is manifested as a seral type from central Idaho northward to northern Idaho, eastern Washington, western Montana and southwestern Alberta. This association is most prominent in west-central and central Montana forests. This association''s elevation range is rather broad, from 1030 to 2015 m (3100-6600 feet). It occupies primarily south- through west-facing, moderate to steep slopes and is usually found on midslope to slope shoulder positions. It also occurs on benches associated with broad ridges. Soils are well-drained and derived from a broad spectrum of parent materials including glacial till and drift, both calcareous and noncalcareous sedimentary types, intrusive and extrusive igneous rock and metamorphic types, particularly quartzite. In one study soil texture ranged from gravelly sandy loams to silts. Ground surfaces have little or no bare soil or rock exposed. The canopy structure ranges from moderately open to closed (>60% cover) with Pinus contorta being strongly dominant in this layer, with lesser amounts of Larix occidentalis and Pseudotsuga menziesii. At mid to upper elevation limits of the type, Abies grandis, Abies lasiocarpa and Picea engelmannii may be minor components of the overstory and major components of the subcanopy. A tall-shrub layer is absent and even scattered individuals are rare. A short-shrub layer dominates the undergrowth with Vaccinium membranaceum being dominant, often exceeding 50% canopy cover; Spiraea betulifolia, Lonicera utahensis, Paxistima myrsinites, Amelanchier alnifolia, and Rosa gymnocarpa are the other high-constancy species of this layer. Dwarf-shrub layer species that occur with consistency include only Vaccinium scoparium and Mahonia repens. The herbaceous layer is generally relatively depauperate with the diagnostic species Xerophyllum tenax being strongly dominant (average cover reported by various studies ranging from 25 to 61%). Only two graminoids occur consistently and are well-represented in cover, Calamagrostis rubescens and Carex geyeri. Other forbs with moderate to high constancy include Arnica cordifolia, Arnica latifolia, Chimaphila umbellata, Orthilia secunda, Thalictrum occidentale, and Viola orbiculata; not all of these forbs have high constancy throughout the range of the type.

Diagnostic Characteristics: No Data Available

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: With the comparatively recent emphasis on developing descriptions of (and keys to) existing vegetation (Grossman et al. 1998), it has yet to be determined at what cover values forest vegetation types will be distinguished one from another when the canopy tree species are mostly seral in nature and have a broad environmental range (broad niche). Pfister et al. (1977) recognized Pinus contorta community types only when no other, more shade-tolerant tree species could be found on site. With Pinus contorta, which is exclusively seral except with respect to some subspecies on unusual substrates or atypical environments, researchers in Glacier National Park took the position that this very shade-intolerant, stand-replacing fire-adapted species should have several times the cover of the next most abundant canopy species for a Pinus contorta type to be recognized. What is really being indicated by this approach are areas having experienced stand-replacing fires (or similar catastrophic disturbance, e.g., clearcutting). Another approach could simply recognize the plurality of tree cover in assigning stands to particular associations treating existing vegetation. The stands representing this type are climax in a number of different tree series including Abies lasiocarpa, Abies grandis, Tsuga mertensiana, and Pseudotsuga menziesii. That this association in fact occurs in the states and USFS Sections listed derives from this writer''s interpretation of constancy/cover tables of various authors/publications; where Pinus contorta is listed as a major seral species the inference has been made that stands quite likely occur on the landscape where this species strongly dominates the upper canopy (often observed throughout northern Idaho and western Montana) (S. Cooper pers. comm.).

Similar NVC Types: No Data Available

note: No Data Available