Name:
Eastern North American Subboreal Bog & Acidic Fen Group
Reference:
NatureServe Biotics 2019
Description:
These <i>Sphagnum</i> and shrub peatlands occur in basins and open peatlands in the Laurentian-Acadian region down to near the glacial boundary in the northeastern and north-central U.S. Unlike the true raised bogs of boreal regions, the vegetation is rarely or not raised above the groundwater level. The nutrient-poor substrate and the reduced throughflow of water create oligotrophic conditions fostering the development of <i>Sphagnum</i> peat and the growth of peatland vegetation. Major physiognomic types include two primary types. First, the ericaceous dwarf-shrub bog, often dominated by <i>Chamaedaphne calyculata</i> (sometimes with distinctive southern and coastal elements such as <i>Gaylussacia dumosa, Ilex glabra</i>, and <i>Morella pensylvanica</i>). Second, tall-shrub thicket peatlands are dominated by deciduous ericaceous shrubs, especially <i>Vaccinium corymbosum</i> (<i>Ilex verticillata</i> can dominate on shallower peat and near the bog border). Graminoids such as <i>Carex oligosperma, Carex magellanica ssp. irrigua, Eriophorum angustifolium, Eriophorum virginicum</i>, and <i>Eriophorum vaginatum</i> are most common, and together these graminoids have greater cover than medium to rich fen graminoid indicators (<i>Carex lasiocarpa, Carex livida, Carex interior, Carex limosa, Muhlenbergia glomerata, Trichophorum alpinum, Eriophorum viridicarinatum</i>). Transitional poor to medium sites may include <i>Myrica gale</i> and <i>Dulichium arundinaceum</i>. Some peatlands may have a sparse tree layer (<10% cover), and stunted (<2 m) trees may be common, usually <i>Picea mariana, Larix laricina</i>, and <i>Acer rubrum</i>. These peatlands are found in colder regions, mostly in areas where glacial stagnation left coarse deposits and glacial depressions (many are "kettleholes"). The basins are generally closed, i.e., without inlets or outlets of surface water, and typically small in area. In deeper basins, the vascular vegetation grows on a <i>Sphagnum</i> mat over water, with no mineral soil development. Species diversity is typically low. Although these peatlands are often called bogs, in most cases they are technically "poor fens," as the vegetation remains in contact with the weakly minerotrophic (nutrient-poor) groundwater.
Accession Code:
urn:lsid:vegbank.org:commConcept:40329-{FB94B7CB-9E34-4301-BF2E-AD009DDD7C3C}
Plot-observations of this Community Concept:
0
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