Common (Translated Scientific) Name: Douglas-fir / Bride''s Bonnet - Common Beargrass Forest

Colloquial Name: No Data Available

Hierarchy Level:  Association

Type Concept: This is a seral, mesic, large-patch to matrix type found in the foothills and montane to lower and even mid-subalpine, relatively cold and dry environments throughout the northern Rocky Mountains and may extend as far west as the Cascade Crest. The associations'' possible elevation range is from 915 to 1800 m (3000-5900 feet), and regardless of the climax series in which it is found, it consistently occurs on south- through west-facing exposures. The range of parent materials is, with the exception of highly unusual substrates like serpentine, literally as great as possible types occurring in the northern Rocky Mountains and northernmost middle Rocky Mountains and may include some ultramafics east of the Cascade Crest. It is difficult to characterize the soils as well, but they are uniformly well-drained and have a low coarse-fragment content, except those sites within the lower to mid-subalpine zone. The overstory is dominated by Pseudotsuga menziesii with a whole host of tree species capable of playing a subordinate role; on warmer sites these include Thuja plicata, Tsuga heterophylla, Abies grandis, and on colder or higher elevation sites are found Abies lasiocarpa, Tsuga mertensiana, and Picea engelmannii. However, the most frequent canopy codominants or associates are the seral species Larix occidentalis, Pinus contorta, and in a restricted portion of the type''s range, Pinus monticola. The tall-shrub component is relatively unimportant, only Alnus viridis ssp. sinuata and Amelanchier alnifolia approach 50% constancy (and have low cover values). The short-shrub layer exhibits greater cover and diversity than the other shrub components with Vaccinium membranaceum, Paxistima myrsinites, Rosa gymnocarpa, Rubus parviflorus, and Spiraea betulifolia being consistently present. Linnaea borealis and Chimaphila umbellata have high constancy in the dwarf-shrub layer. Bromus vulgaris (or Bromus ciliatus) are the only graminoids of note. The diagnostic forbs Clintonia uniflora, Xerophyllum tenax, and Tiarella trifoliata naturally have high constancy and/or cover, however, a number of other forbs also exhibit high constancy, including Arnica latifolia, Aralia nudicaulis, Adenocaulon bicolor, Coptis occidentalis, Cornus canadensis, Galium triflorum, Goodyera oblongifolia, Maianthemum stellatum, Osmorhiza berteroi, Pedicularis racemosa, Orthilia secunda, Thalictrum occidentale, Trillium ovatum, and Viola orbiculata.

Diagnostic Characteristics: No Data Available

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: This association defines an extremely broad environmental range due to the approach of defining as unique associations those communities that would formerly have been subsumed within a number of different climax or potential vegetation types; in the case of this association it is a successional stage in environments as mild and wet (defining a Pacific maritime climatic influence) as those supporting Thuja plicata or Tsuga heterophylla / Clintonia uniflora associations (and permutations) to those of the lower subalpine zone characterized by Abies lasiocarpa, Abies grandis, Tsuga mertensiana, and even Picea engelmannii / Clintonia uniflora forest associations. 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 Pseudotsuga 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 by this author throughout northern Idaho and western Montana). It should also be noted that this type is probably less common in zones where Thuja plicata and Tsuga heterophylla are the climax dominants because, following disturbance in these zones, the climax trees are quick to reclaim the site, i.e., they comprise a significant cover of the earliest forested successional stages. The crosswalking for this type is incomplete, and it may well occur west of the Cascade Crest in Oregon and Washington.

Similar NVC Types: No Data Available

note: No Data Available