Name:
Pinus contorta / Menziesia ferruginea / Clintonia uniflora Forest
Reference:
Western Ecology Working Group of...
Description:
This seral, large-patch to matrix lodgepole pine forest occupies the relatively cold and dry environments across a number of climax tree series and associated geographic regions. Thus, this cold mesic type is found throughout the northern Rocky Mountains and may extend as far west as the Cascade Crest on environments characterized as montane to lower and even mid-subalpine. The association's possible elevation range is from 915 to 1800 m (3000-5700 feet), and it consistently occurs on cool northwest- through east-facing slopes with moderate to extreme degrees of slope. It is generally associated with collecting positions from midslope to toeslope and foot-slopes when it occurs in subalpine zones, but in the more mesic montane zones, it can be found on all positions. The range of parent materials is 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. The soils are acidic to very acidic, uniformly moderately well-drained to well-drained and have a highly variable coarse-fragment content. Ground surfaces have virtually no exposed rock or bare soil, and duff accumulations vary from moderate to deep. The overstory canopy is often on the cusp between open and closed (defined as 60%) and decidedly dominated by Pinus contorta, but its cover is often less than 40%. A number of other conifers may be present; on warmer sites these include Thuja plicata, Tsuga heterophylla, and 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, Pseudotsuga menziesii, and in a restricted portion of the type's range Pinus monticola. Menziesia ferruginea conspicuously dominates the tall-shrub layer. Alnus viridis ssp. sinuata and Taxus brevifolia are the only other tall shrubs consistently present. The short-shrub layer exhibits greater diversity with Vaccinium membranaceum, Paxistima myrsinites, Rosa gymnocarpa, Rubus parviflorus, and Spiraea betulifolia being consistently present. Linnaea borealis, Chimaphila umbellata, and Vaccinium scoparium have high constancy in the dwarf-shrub layer. Bromus vulgaris (or Bromus ciliatus) are the only graminoids of note. The diagnostic forbs Clintonia uniflora and Tiarella trifoliata have high constancy (both approaching 100%) and/or cover; however, a number of other forbs also exhibit high constancy across this type's range, including Arnica latifolia, (Arnica cordifolia at lower elevations), Coptis occidentalis, Cornus canadensis, Galium triflorum, Goodyera oblongifolia, Maianthemum stellatum, Osmorhiza berteroi (= Osmorhiza chilensis), Orthilia secunda (= Pyrola secunda), Thalictrum occidentale, Trillium ovatum, Viola orbiculata, and Xerophyllum tenax. As with the forb layer, the bryoid layer cover apparently varies inversely with the degree of canopy closure.
Accession Code:
VB.CC.28022.PINUSCONTORTAME
Plot-observations of this Community Concept:
0
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