Northern Ontario Plant Database

Northern Ontario Vegetation Type (V-type)

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NW-V7: Trembling Aspen - Balsam Fir / Balsam Fir Shrub

Summary: A two-tiered mixedwood stand dominated by trembling aspen in the upper canopy and balsam fir in the subcanopy. Balsam fir also dominates the regeneration. The relatively sparse shrub layer contains a variety of tall and low shrubs, although mountain maple is less abundant in this type than in NW-V6 and NW-V8. Occasional sites will contain abundant amounts of beaked hazel and mountain alder. Bush honeysuckle and prickly wild rose are the most common species in the low shrub layer.

The very species-rich herb layer is dominated by wild sarsaparilla and the characteristic boreal forest species; largeleaf aster, rose twisted-stalk, and naked mitrewort also occur in the herb layer. The presence of kidneyleaf violet and sweet coltsfoot indicate sites with calcareous soils. The forest floor is covered by broadleaf litter with small patches of feathermoss.

Soil & Ecosite Types: The Trembling Aspen-Balsam Fir/Balsam Fir Shrub Vegetation Type (NW-V7) occur most commonly on Ecosite Types ES 16 (Hardwood-Fir-Spruce Mixedwood, sandy soil), ES 19 (Hardwood-Fir-Spruce Mixedwood, fresh, sandy- coarse loamy soil), ES 28 (Hardwood-Fir-Spruce Mixedwood, fresh, silty soil), and ES 29 (Hardwood-Fir-Spruce Mixedwood, fresh, fine loamy-clayey soil) on deep, fresh, well-drained, fine-textured mineral soils (mainly S4 and S6). Also, this type occurs more frequently than Trembling Aspen (White Birch)-Balsam Fir/Mountain Maple (NW-V6) on calcareous, fine-textured lacustrine deposits. The smaller quantities of mountain maple and greater crown closure can be used to distinguish type NW-V7 from the Trembling Aspen (White Birch)/Mountain Maple types (NW-V6 and NW-V8).

Note: The percentage of sample plots that contained overstorey tree species is given in square brackets after each scientific name. Other species are listed in order of frequency, according to the NW-FEC manual.

Trees:

overstorey:

balsam fir (Abies balsamea) [10]
trembling aspen (Populus tremuloides) [10]
white birch (Betula papyrifera) [5]
white spruce (Picea glauca) [3]
black spruce (Picea mariana) [2]
jack pine (Pinus banksiana) [1]

regeneration:

balsam fir (Abies balsamea)
trembling aspen (Populus tremuloides)

Shrubs:

tall shrubs:

mountain maple (Acer spicatum)
beaked hazel (Corylus cornuta)
showy mountain ash (Sorbus decora)

low shrubs:

bush honeysuckle (Diervilla lonicera)
prickly wild rose (Rosa acicularis)

Dwarf Shrubs & Herbs:

dwarf shrubs:

dwarf raspberry (Rubus pubescens)
twinflower (Linnaea borealis)

forbs:

wild lily-of-the-valley (Maianthemum canadense)
wild sarsaparilla (Aralia nudicaulis)
bunchberry (Cornus canadensis)
bluebead lily (Clintonia borealis)
largeleaf aster (Eurybia macrophylla)
rose twisted-stalk (Streptopus lanceolatus)
starflower (Trientalis borealis)
kidneyleaf violet (Viola reinfolia)
naked mitrewort (Mitella nuda)
sweet coltsfoot (Petasites frigidus var. palmatus)
wood anemone (Anemone quinquefolia)
fragrant bedstraw (Galium triflorum)

Bryophytes:

Schreber's feathermoss (Pleurozium schreberi)
shaggy moss (Rhytidiadelphus triquetrus)