Northern white cedar - balsam fir swamp (S2)
Northern white cedar - balsam fir swamp is a cedar-dominated peatland community of northern New Hampshire. It develops on weakly acidic to circumneutral organic soils. In mature examples, the overstory canopy reaches heights of 40 to 60 feet. There are also occasional to frequent leaning trees and blowdowns, moderately well developed cedar tree subcanopies, sparse shrub understories, well-developed hummock-hollow topography, dense carpets of diverse mosses and liverworts, and sparse to moderate herb cover.
Characteristic Vegetation: Northern white cedar (Thuja occidentalis) is the dominant tree, with lesser to equal amounts of balsam fir (Abies balsamea). Trees that may be present in lesser abundances include black ash (Fraxinus nigra), yellow birch (Betula alleghaniensis), red maple (Acer rubrum), white spruce (Picea glauca), eastern larch (Larix laricina), red spruce (Picea rubens), and black spruce (Picea mariana).
Characteristic shrubs and herbs of this community include Canadian honeysuckle (Lonicera canadensis), witherod (Viburnum nudum var. cassinoides), mountain holly (Nemopanthus mucronatus), red osier dogwood (Cornus sericea), mountain maple (Acer spicatum), bunchberry (Cornus canadensis), creeping snowberry (Gaultheria hispidula), twinflower (Linnaea borealis), Canada yew (Taxus canadensis), naked miterwort (Mitella nuda), cinnamon fern (Osmunda cinnamomea), long-stalked sedge (Carex pedunculata), three-seeded sedge (Carex trisperma var. trisperma), delicate sedge (Carex leptalea), inflated sedge (Carex intumescens), one-sided shinleaf (Orthilia secunda), blunt-leaved orchid (Platanthera obtusata), American alder buckthorn (Rhamnus alnifolia), goldthread (Coptis trifolia), northern wood sorrel (Oxalis montana), starflower (Trientalis borealis), long beech fern (Phegopteris connectilis), and northern lady fern (Athyrium filix-femina var. angustum). Bryophytes are diverse and form a nearly constant ground cover.
Potential rare plant species of these cedar swamps (often found in fen-like openings within the swamps) include several varieties of lady’s slippers (Cypripedium reginae, C. parviflorum, C. pubescens, and C. arietinum) , sweet coltsfoot (Petasites frigidus), chestnut sedge (Carex castanea), fairy slipper (Calypso bulbosa), and Loesel’s twayblade (Liparis loeselii).
Northern white cedar is primarily a boreal tree species. It occurs frequently in northern New Hampshire, but only sparingly south of the White Mountain region. It is often associated with other conifers, and to a lesser extent northern hardwoods, although it can also occur in nearly pure, closed canopy stands. In addition to this community, several other northern white cedar swamp natural community types also occur in the northern part of the state.
Good examples of this community can be seen at Hurlbert Swamp Preserve (Stewartstown),
Northern white cedar seepage forests often occur as part of near-boreal minerotrophic peat swamp systems.
1. NWC - balsam fir swamp at Hurlbert Swamp. 2. NWC - balsam fir swamp along Beaver Brook.
(photos by Ben Kimball)
Northern white cedar - balsam fir swamp at Cape Horn State Forest (photo by Dan Sperduto)