Peatland Atlantic White-Cedar Forests
In Virginia, these coniferous forests are confined to saturated, oligotrophic, Coastal Plain peatlands. Peatland Atlantic White-Cedar Forests are endemic to terraces of the Embayed Region of extreme southeastern Virginia and northeastern North Carolina. Habitats are non-riverine wetland flats with deep organic soils (e.g., Great Dismal Swamp, Cities of Suffolk and Chesapeake) and remote peat flats beyond the range of wind-tidal flooding along the North Landing River (City of Virginia Beach). Atlantic white-cedar forests usually occupy relatively wet peatlands subject to infrequent catastrophic fires. Dense, even-aged stands become established when such fires remove most vegetation and debris, exposing suitable seedbeds. Throughout their maturation, these stands accumulate extensive dead wood and inflammable duff, making them increasingly susceptible to another stand-killing fire. Atlantic white-cedar (Chamaecyparis thyoides) dominates the overstory, sometimes with red maple (Acer rubrum), swamp tupelo (Nyssa biflora), or pines (Pinus serotina and Pinus taeda) as minor associates. Red bay (Persea palustris), sweetbay magnolia (Magnolia virginiana var. virginiana), sweet pepperbush (Clethra alnifolia), big gallberry (Ilex coriacea), inkberry (Ilex glabra), shining fetterbush (Lyonia lucida), and poison ivy (Toxicodendron radicans var. radicans) are common small trees and shrubs. Cinnamon fern (Osmundastrum cinnamomeum) and Virginia chain fern (Woodwardia virginica) are common herbs, while (Sphagnum spp.) and other mosses abundantly cover the ground.
Peatland Atlantic White-Cedar Forests are floristically similar to both Pond Pine Woodlands and Pocosins and the Mixed Evergreen Type of Non-Riverine Swamp Forest. They differ from both in overstory dominance and lower shrub density, and an association with large peatlands that formerly were subject to catastrophic fires at long return intervals. Peatland Atlantic white-cedar forests are globally rare and now reduced to small remnants of their former distribution by extensive logging and fire reduction. Because of these disturbances and extensive ditching, many former stands in the Great Dismal Swamp have been converted to Non-Riverine Swamp Forests dominated by red maple and swamp tupelo. Atlantic white-cedar is the larval host of the rare butterfly Hessel's hairstreak (Mitoura hesseli), which has been recorded in the Great Dismal Swamp.
References: Dabel and Day (1977), Day (1985), Dean (1969), Fleming and Moorhead (1998), Frost (1995), Stevens and Patterson (1998), Train and Day (1982).