Name:
Eastern North American Boreal Forest Macrogroup
Reference:
NatureServe Biotics 2019
Description:
This macrogroup describes upland boreal forests in eastern Canada, ranging from northwestern Ontario to Newfoundland and Labrador. On mesic, well-drained sites with moderate nutrient status, these are primarily closed coniferous forests, although hardwood and mixed conifer-hardwood forests are also common. Dominant tree species include <i>Abies balsamea, Betula papyrifera, Picea glauca, Picea mariana, Pinus banksiana</i>, and <i>Populus tremuloides</i>. Two CNVC sub-macrogroups distinguish "Atlantic" boreal forests from those more characteristic of Ontario and western Quebec. On nutrient-poor sites, understory species are dominated by the ericaceous species <i>Kalmia angustifolia, Ledum groenlandicum, Vaccinium angustifolium</i>, and <i>Vaccinium myrtilloides</i>. On richer sites, forb species such as <i>Clintonia borealis, Aralia nudicaulis, Trientalis borealis</i>, and shrubs such as <i>Acer spicatum</i> and <i>Sorbus</i> spp. are common. Feathermoss cover is dominated by <i>Pleurozium schreberi</i>, although <i>Hylocomium splendens</i> becomes more prevalent on moister, richer sites. This macrogroup occurs within the humid to perhumid boreal climate of eastern Canada. In the "Ontario and Quebec" boreal, the humid continental climate supports an active fire regime, which results in frequent, and often extensive, post-fire stands of <i>Pinus banksiana</i>, usually in combination with <i>Picea mariana</i>. <i>Populus tremuloides</i> is also important in this sub-macrogroup. The "Atlantic" sub-macrogroup is characterized by dominance of <i>Picea mariana, Abies balsamea</i>, and white birch, at the expense of <i>Pinus banksiana</i> and <i>Populus tremuloides</i>. In the perhumid to oceanic climates of eastern Quebec and Newfoundland and Labrador, fire frequency is reduced and stand dynamics are largely driven by insect epidemics, especially spruce budworm (<i>Choristoneura fumiferana</i>) which primarily attacks <i>Abies balsamea</i>. Picea mariana is maintained in combination with fir on the landscape by regular, but less frequent, stand-replacing fire. <i>Hylocomium splendens</i> becomes more important in the moss layer in the "Atlantic" boreal and the humidity-loving hepatic <i>Bazzania trilobata</i> appears. Regional geologic and topographic features produce an array of local site conditions. Most of the area occupied by this macrogroup is underlain by Canadian Shield bedrock, although high elevations of the Gaspé Peninsula and the varied geology of insular Newfoundland are exceptions. Soils are typically Brunisols or podzols developed in glacial sediments.
Accession Code:
urn:lsid:vegbank.org:commConcept:40796-{11819172-0DC4-41B4-A4D0-1E540CDCADB0}
Plot-observations of this Community Concept:
0
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