Name:
Tsuga canadensis - Betula alleghaniensis / Ilex verticillata / Sphagnum spp. Forest
Reference:
Eastern Ecology Working Group of...
Description:
These hemlock-hardwood swamps are common throughout most of New England and New York, mostly in glaciated areas south of spruce-fir forest regions. Most are mixed-canopy wetland forests, but in some may be strongly coniferous. They occur in poorly drained basins over bedrock or compacted till. "Pocket swamps," small isolated basins in upland forests, are one setting, and these swamps also occur adjacent to streams and lakes in larger basins. The acidic, organic soils remain saturated for most or all of the growing season; they may partially dry out, particularly in smaller basins. Canopy closure is nearly complete, and shrubs are sparse. The herbaceous layer may be well-developed, with ferns especially characteristic. Bryophyte cover varies, but is usually extensive. Tsuga canadensis is either canopy dominant or is mixed with other trees including Acer rubrum, Betula alleghaniensis, Pinus strobus, Nyssa sylvatica, and Fraxinus nigra. Scattered shrubs include Vaccinium corymbosum, Ilex verticillata, Lyonia ligustrina, Nemopanthus mucronatus, and Viburnum nudum var. cassinoides. Osmunda cinnamomea, Osmunda regalis, and Onoclea sensibilis are prominent ferns; associated herbs include Carex folliculata, Carex trisperma, Carex disperma, Maianthemum canadense, Coptis trifolia, Dryopteris cristata, Rubus pubescens, and Mitchella repens. Bryophytes include Sphagnum girgensohnii, Sphagnum palustre, and other Sphagnum species, as well as Pleurozium schreberi and Bazzania trilobata. These forests lack the species of more southerly affinity, such as Rhododendron maximum or Liriodendron tulipifera, that characterize hemlock swamps to the south, which are covered by Tsuga canadensis / Rhododendron maximum / Sphagnum spp. Forest (CEGL006279). Mixed expression of these swamps may be similar in canopy composition to Betula alleghaniensis - Acer rubrum - (Tsuga canadensis, Abies balsamea) / Osmunda cinnamomea Forest (CEGL006380); those are mineral-soil wetlands in seepage-influenced areas, typically at wetland-upland ecotones, and usually occur on slopes rather than in basins. Acer rubrum - Nyssa sylvatica - Betula alleghaniensis / Sphagnum spp. Forest (CEGL006014) is ecologically similar but is more strongly deciduous, with limited hemlock.
Accession Code:
VB.CC.25064.TSUGACANADENSIS
Plot-observations of this Community Concept:
0
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