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CEGL000500 Tsuga mertensiana - Abies amabilis / Xerophyllum tenax Forest
Type Concept Sentence: No Data Available
Common (Translated Scientific) Name: Mountain Hemlock - Pacific Silver Fir / Common Beargrass Forest
Colloquial Name: No Data Available
Hierarchy Level: Association
Type Concept: Endemic to part of the upper elevations of the eastern Cascades of Washington, this association is restricted to a few sections of Bailey''s Eastern Cascades (M242C) between Snoqualmie Pass and Mount Adams. This is a high-elevation, closed-canopy forest association composed of trees that are rarely over 200 years old. These are some of the driest sites supporting Tsuga mertensiana in the Cascades. Found in the mid elevational range of other Tsuga mertensiana communities, these sites are gravelly, usually on ridges and upper slopes and associated with heavy snow accumulation. Tsuga mertensiana is always present and usually the most abundant tree in the upper canopy. Larix occidentalis, Pinus contorta var. latifolia, Abies lasiocarpa, or Abies amabilis can be abundant. Tsuga mertensiana, Abies lasiocarpa, and Abies amabilis are the most common tree species in lower canopy. The evergreen perennial forb Xerophyllum tenax is the most common and abundant species in the undergrowth. Vaccinium myrtillus and Paxistima myrsinites are common shrub associates. Few forbs occur in this community.
Diagnostic Characteristics: No Data Available
Rationale for Nominal Species or Physiognomic Features: No Data Available
Classification Comments: This is described within a PNV-based classification as Tsuga mertensiana / Xerophyllum tenax - Vaccinium myrtillus association by Lillybridge et al. (1995). Those authors say this is similar to the Tsuga mertensiana phase of Abies amabilis / Xerophyllum tenax in Franklin et al. (1988) on Mount Rainier National Park (WANHP crosswalk instead includes Franklin''s phase in ~Tsuga mertensiana - Abies amabilis / Vaccinium membranaceum - Xerophyllum tenax Forest (CEGL000515)$$ because it has high cover of Tsuga heterophylla and low cover of Tsuga mertensiana, Abies lasiocarpa, and no Picea engelmannii or Vaccinium myrtillus). Lillybridge et al. (1995) say some plots of Tsuga mertensiana / Xerophyllum tenax - Vaccinium myrtillus are similar to Abies amabilis / Vaccinium membranaceum / Xerophyllum tenax of Hemstrom et al. (1982) (WANHP crosswalk instead includes most of Hemstrom''s association in CEGL000515 because of the high importance of Abies procera and Pseudotsuga menziesii, and no Vaccinium myrtillus). Lillybridge et al. (1995) assessment that "samples are floristically richer than most of the other plots may be separated after further analysis" is interpreted here to mean that those samples (subset of plots in Tsuga mertensiana / Xerophyllum tenax - Vaccinium myrtillus) are more western plots which likely have affinity to CEGL000515). This interpretation modifies the 1994 crosswalk by Chappell, Kagan and Crawford of all published Abies amabilis and Tsuga mertensiana who only recognized the Tsuga mertensiana / Xerophyllum tenax of Williams and Smith (1990) which was the draft of Lillybridge et al. (1995).
Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: No Data Available
Floristics: This is a high-elevation, closed-canopy forest association composed of trees that are rarely over 200 years old. Tsuga mertensiana is always present and usually the most abundant tree in the upper canopy. Larix occidentalis, Pinus contorta var. latifolia, Abies lasiocarpa, or Abies amabilis can be abundant. Tsuga mertensiana, Abies lasiocarpa, and Abies amabilis are the most common tree species in lower canopy. The evergreen perennial forb Xerophyllum tenax is the most common and abundant species in the undergrowth. Vaccinium myrtillus and Paxistima myrsinites are common shrub associates. Few forbs occur in this community.
Dynamics: No Data Available
Environmental Description: These are some of the driest sites supporting Tsuga mertensiana in the Cascades. Found in the mid elevational range of other Tsuga mertensiana communities, these sites are gravelly, usually on ridges and upper slopes and associated with heavy snow accumulation.
Geographic Range: Evidently an endemic to portions of the upper elevations of the eastern Cascades of Washington, it is restricted to mostly south of Omernik''s North Cascades ecoregion and in the eastern Cascades slope level 3, and in a few section of Bailey''s eastern Cascades (M242C) in Washington.
Nations: US
States/Provinces: WA
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.683936
Confidence Level: Low
Confidence Level Comments: No Data Available
Grank: G3
Greasons: No Data Available
| Type | Name | Database Code | Classification Code |
|---|---|---|---|
| Class | 1 Forest & Woodland Class | C01 | 1 |
| Subclass | 1.B Temperate & Boreal Forest & Woodland Subclass | S15 | 1.B |
| Formation | 1.B.2 Cool Temperate Forest & Woodland Formation | F008 | 1.B.2 |
| Division | 1.B.2.Nd Vancouverian Forest & Woodland Division | D192 | 1.B.2.Nd |
| Macrogroup | 1.B.2.Nd.4 California Red Fir - Mountain Hemlock - Sierra Lodgepole Pine Forest Macrogroup | M025 | 1.B.2.Nd.4 |
| Group | 1.B.2.Nd.4.c Mountain Hemlock - Pacific Silver Fir - Alaska-cedar Wood Group | G849 | 1.B.2.Nd.4.c |
| Alliance | A3723 Mountain Hemlock - Pacific Silver Fir Forest & Woodland Alliance | A3723 | 1.B.2.Nd.4.c |
| Association | CEGL000500 Mountain Hemlock - Pacific Silver Fir / Common Beargrass Forest | CEGL000500 | 1.B.2.Nd.4.c |
Concept Lineage: No Data Available
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: ? Tsuga mertensiana / Xerophyllum tenax - Vaccinium myrtillus (Lillybridge et al. 1995) [TSME/XETE-VAMY ASSOCIATION CMF131]
? Tsuga mertensiana phase of Abies amabilis / Xerophyllum tenax (Franklin et al. 1988)
? Pacific silver fir / big huckleberry / beargrass (ABAM/VAME/XETE) (Hemstrom et al. 1982) [Pacific silver fir / big huckleberry / beargrass (ABAM/VAME/XETE)]
? Tsuga mertensiana phase of Abies amabilis / Xerophyllum tenax (Franklin et al. 1988)
? Pacific silver fir / big huckleberry / beargrass (ABAM/VAME/XETE) (Hemstrom et al. 1982) [Pacific silver fir / big huckleberry / beargrass (ABAM/VAME/XETE)]
- Bailey, R. G. 1998. Ecoregion map of North America: Explanatory note. Miscellaneous Publication Number 1548, USDA Forest Service. 10 pp.
- Bourgeron, P. S., and L. D. Engelking, editors. 1994. A preliminary vegetation classification of the western United States. Unpublished report. The Nature Conservancy, Western Heritage Task Force, Boulder, CO. 175 pp. plus appendix.
- Franklin, J. F., W. H. Moir, M. A. Hemstrom, S. E. Greene, and B. G. Smith. 1988. The forest communities of Mount Rainier National Park. USDI National Park Service. Scientific Monograph Series 19. Washington, DC. 194 pp.
- Hemstrom, M. A., W. H. Emmingham, N. M. Halverson, S. E. Logan, and C. Topik. 1982. Plant association and management guide for the pacific silver fir zone, Mt. Hood and Willamette national forests. R6-Ecol 100-1982a. USDA Forest Service, Pacific Northwest Region, Portland, OR. 104 pp.
- Lillybridge, T. R., B. L. Kovalchik, C. K. Williams, and B. G. Smith. 1995. Field guide for forested plant associations of the Wenatchee National Forest. General Technical Report PNW-GTR-359. USDA Forest Service, Pacific Northwest Research Station, Portland, OR. 335 pp.
- Omernik, J. M. 1995. Ecoregions: A framework for environmental management. Pages 49-62 in: W. S. Davis and T. P. Simon, editors. Biological assessment and criteria: Tools for water resource planning and decision making. Lewis Publishers, Boca Raton, FL.
- WNHP [Washington Natural Heritage Program]. 2018. Unpublished data files. Washington Natural Heritage Program, Department of Natural Resources, Olympia, WA.
- Western Ecology Working Group of NatureServe. No date. International Ecological Classification Standard: International Vegetation Classification. Terrestrial Vegetation. NatureServe, Boulder, CO.
- Williams, C. K., and B. G. Smith. 1990. Forested plant associations of the Wenatchee National Forest. Unpublished draft prepared by the USDA Forest Service, Pacific Northwest Region, Portland, OR. 217 pp.