I. Forest 10 I. A n a. Lowland tropical or subtropical seasonal evergreen forest 10




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I.B.2.N.a. Lowland or submontane cold-deciduous forest

A.266 Betula alleghaniensis - Fagus grandifolia - Aesculus flava Forest Alliance


Yellow Birch - American Beech - Yellow Buckeye Forest Alliance

Alliance Concept

Summary: This alliance includes montane forests, mainly of the southern and central Appalachians, dominated by Fagus grandifolia, Betula alleghaniensis, and Aesculus flava, occurring in combination or with strong dominance by one of these species. Other species that may form a typically minor canopy component include Acer saccharum, Betula lenta, Halesia tetraptera var. monticola, Picea rubens, Prunus serotina var. serotina, Quercus rubra, and Tilia americana var. heterophylla. Subcanopy species can include small stems of canopy species as well as Acer spicatum, Acer pensylvanicum, Amelanchier laevis, and Sorbus americana. Shrub density varies between associations, ranging from very high to entirely lacking. Common species in the shrub and sapling strata include Acer pensylvanicum, Acer spicatum, Amelanchier arborea var. austromontana, Aristolochia macrophylla, Cornus alternifolia, Crataegus punctata, Hydrangea arborescens, Ilex montana, Ribes cynosbati, Ribes rotundifolium, Ribes glandulosum, Rubus allegheniensis, Rubus canadensis, Vaccinium erythrocarpum, and Viburnum lantanoides. The composition of herbaceous strata varies between associations. Variability in the herbaceous stratum may be related to aspect, elevation, and soil-nutrient status. Forests on drier, south-facing sites (often open convex slopes) typically have dense herbaceous cover, often approaching 100% coverage, and dominated by species of Carex (Carex aestivalis, Carex brunnescens ssp. sphaerostachya, Carex debilis var. rudgei, Carex intumescens, Carex pensylvanica), while more mesic sites have herbaceous strata dominated by large forbs and patches of ferns, with lesser amounts of sedges. In some forests, seepage areas are common, producing wet microhabitats with unique species assemblages (Chelone lyonii, Circaea alpina, Rudbeckia laciniata, Impatiens pallida, and Monarda didyma). Woody vines, and vining shrubs, may be common, especially in boulderfield associations. Other typical herbaceous species for this alliance include Ageratina altissima var. roanensis, Anemone quinquefolia, Angelica triquinata, Arisaema triphyllum, Eurybia chlorolepis (= Aster chlorolepis), Athyrium filix-femina ssp. asplenioides, Cardamine clematitis, Actaea podocarpa (= Cimicifuga americana), Actaea racemosa (= Cimicifuga racemosa), Circaea alpina, Claytonia caroliniana, Clintonia borealis, Prosartes lanuginosa (= Disporum lanuginosum), Dryopteris campyloptera, Dryopteris intermedia, Dryopteris marginalis, Erythronium umbilicatum ssp. monostolum, Hylocomium splendens, Luzula acuminata, Maianthemum canadense, Medeola virginiana, Oxalis montana, Phacelia bipinnatifida, Phacelia fimbriata, Poa alsodes, Prenanthes altissima, Prenanthes roanensis, Rugelia nudicaulis, Saxifraga micranthidifolia, Solidago curtisii (= Solidago caesia var. curtisii), Solidago glomerata, Stellaria corei, Stellaria pubera, Streptopus lanceolatus var. roseus (= Streptopus roseus), Tiarella cordifolia, Thelypteris noveboracensis, and Trillium erectum. These forests occur in a cool, humid climate, typically at high elevations (3500-6000 feet; 1066-1828 m) on a variety of sites, from upper concave slopes and steep, periglacial boulderfields and talus slopes, to flat ridgetops and saddles between ridges. Associations will vary with elevation, latitude, and geology and occur as small to large patches surrounded by other forest types, montane grasslands, or shrublands.

Environment: These forests occur in a cool, humid climate, typically at high elevations (3500-6000 feet; 1066-1828 m) on a variety of sites, from upper concave slopes and steep, periglacial boulderfields and talus slopes, to flat ridgetops and saddles between ridges. Associations will vary with elevation, latitude, and geology and occur as small to large patches surrounded by other forest types, montane grasslands, or shrublands.

Vegetation: This alliance includes montane forests dominated by Fagus grandifolia, Betula alleghaniensis, and Aesculus flava, occurring in combination or with strong dominance by one of these species. Other species that may form a typically minor canopy component include Acer saccharum, Betula lenta, Halesia tetraptera var. monticola, Picea rubens, Prunus serotina var. serotina, Quercus rubra, and Tilia americana var. heterophylla. Subcanopy species can include small stems of canopy species as well as Acer spicatum, Acer pensylvanicum, Amelanchier laevis, and Sorbus americana. Shrub density varies between associations, ranging from very high to entirely lacking. Common species in the shrub and sapling strata include Acer pensylvanicum, Acer spicatum, Amelanchier arborea var. austromontana, Aristolochia macrophylla, Cornus alternifolia, Crataegus punctata, Hydrangea arborescens, Ilex montana, Ribes cynosbati, Ribes rotundifolium, Ribes glandulosum, Rubus allegheniensis, Rubus canadensis, Vaccinium erythrocarpum, and Viburnum lantanoides. The composition of herbaceous strata varies between associations. Variability in the herbaceous stratum may be related to aspect, elevation, and soil-nutrient status. Forests on drier, south-facing sites (often open convex slopes) typically have dense herbaceous cover, often approaching 100% coverage, and dominated by species of Carex (Carex aestivalis, Carex brunnescens ssp. sphaerostachya, Carex debilis var. rudgei, Carex intumescens, Carex pensylvanica), while more mesic sites have herbaceous strata dominated by large forbs and patches of ferns, with lesser amounts of sedges. In some forests, seepage areas are common, producing wet microhabitats with unique species assemblages (Chelone lyonii, Circaea alpina, Rudbeckia laciniata, Impatiens pallida, and Monarda didyma). Woody vines, and vining shrubs, may be common, especially in boulderfield associations. Other typical herbaceous species for this alliance include Ageratina altissima var. roanensis, Anemone quinquefolia, Angelica triquinata, Arisaema triphyllum, Eurybia chlorolepis (= Aster chlorolepis), Athyrium filix-femina ssp. asplenioides, Cardamine clematitis, Actaea podocarpa (= Cimicifuga americana), Actaea racemosa (= Cimicifuga racemosa), Circaea alpina, Claytonia caroliniana, Clintonia borealis, Prosartes lanuginosa (= Disporum lanuginosum), Dryopteris campyloptera, Dryopteris intermedia, Dryopteris marginalis, Erythronium umbilicatum ssp. monostolum, Hylocomium splendens, Luzula acuminata, Maianthemum canadense, Medeola virginiana, Oxalis montana, Phacelia bipinnatifida, Phacelia fimbriata, Poa alsodes, Prenanthes altissima, Prenanthes roanensis, Rugelia nudicaulis, Saxifraga micranthidifolia, Solidago curtisii (= Solidago caesia var. curtisii), Solidago glomerata, Stellaria corei, Stellaria pubera, Streptopus lanceolatus var. roseus (= Streptopus roseus), Tiarella cordifolia, Thelypteris noveboracensis, and Trillium erectum.

Dynamics:

Similar Alliances: Acer saccharum - Betula alleghaniensis - (Fagus grandifolia) Forest Alliance (A.216)--includes northern hardwood forests of the Alleghenies and north which lack many of the species found in the southern Appalachian forests, and are overall less species-rich. Fagus grandifolia - Acer saccharum - (Liriodendron tulipifera) Forest Alliance (A.227)--includes forests dominated by Fagus grandifolia but not occurring in a montane landscape (where elevation is the primary environmental gradient). Fagus grandifolia - Quercus alba Forest Alliance (A.228)--includes forests dominated by Fagus grandifolia but not occurring in a montane landscape (where elevation is the primary environmental gradient). Fagus grandifolia - Quercus rubra - Quercus alba Forest Alliance (A.229)--includes forests dominated by Fagus grandifolia but not occurring in a montane landscape (where elevation is the primary environmental gradient). Impatiens (capensis, pallida) - Monarda didyma Saturated Herbaceous Alliance (A.1690) Picea rubens - Betula alleghaniensis Forest Alliance (A.384)--includes montane forests of the Appalachians with a mixed evergreen-deciduous canopy.

Similar Alliance Comments:

Alliance Distribution

Range: Forests in this alliance are found in the high-elevation regions of the Blue Ridge from West Virginia south to northern Georgia and may extend into the adjacent Ridge and Valley and Appalachian Plateau provinces. This alliance is found in Georgia, Kentucky, North Carolina, Tennessee, Virginia, and West Virginia.

Nations: US

Subnations: GA, KY, NC, TN, VA, WV

TNC Ecoregions: 50:C, 51:C, 59:C

USFS Ecoregions: M221Aa:CCC, M221B:C?, M221Cc:CCC, M221Da:CCC, M221Db:CCC, M221Dc:CCC, M221Dd:CCC

Federal Lands: NPS (Blue Ridge Parkway, Cumberland Gap, Great Smoky Mountains); USFS (Chattahoochee, Cherokee, George Washington, Jefferson, Nantahala, Pisgah, Sumter?)

Alliance Sources

Author(s): D.J. Allard, mod. K.D. Patterson

References: Allard 1990, Ambrose 1990a, Bratton 1975, Brown 1941, Chafin and Jones 1989, Davis 1930, Dellinger unpubl. data 1992, Evans 1991, Evans pers. comm., Eyre 1980, Fuller 1977, Golden 1974, Golden 1981, Malter 1977, McLeod 1988, Pittillo and Smathers 1979, Pyne 1994, Ramseur 1960, Rawinski 1992, Rawinski et al. 1994, Rheinhardt 1981, Russell 1953, Schafale and Weakley 1990, Schofield 1960, Singer et al. 1984, Stamper 1976, Wharton 1978, White et al. 1993, Whittaker 1956, Wood 1975
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