Tidal Shrub Swamps
This group comprises tidally flooded and wind-tidally flooded shrublands of estuarine rivers and embayments. Tidal shrub swamps range along Atlantic and Gulf coasts from Maine to Texas. In Virginia, they represent diverse vegetation that frequently occurs in fringes or ecotones between emergent tidal wetlands and swamp forests or uplands. Examples also occur on depositional islands in large meanders of tidal rivers. Several community types have been classified, including a strictly freshwater type dominated by smooth alder (Alnus serrulata) and black willow (Salix nigra); wax myrtle (Morella cerifera) and/or Carolina willow (Salix caroliniana)-dominated shrublands of lunar-tidal and wind-tidal oligohaline systems, and a marsh-elder (Iva frutescens)-dominated shrubland of lunar-tidal, mesohaline systems. Additional shrubs of freshwater and oligohaline stands include buttonbush (Cephalanthus occidentalis), swamp rose (Rosa palustris), silky dogwood (Cornus amomum), arrow-wood (Viburnum dentatum var. dentatum), winterberry (Ilex verticillata), and poison ivy (Toxicodendron radicans var. radicans), while high-tide bush (Baccharis halimifolia) is a frequent associate of the mesohaline types. The herbaceous flora associated with tidal shrub swamps is very diverse and typically contains species characteristic of both tidal marshes and swamp forests. The ecological dynamics, state-wide distribution, and conservation status of communities in this group are poorly known.
References: Coulling (2002), Fleming and Moorhead (1998), McCoy and Fleming (2000).
Click on the images below to open a larger image in a separate window.A wind-tidal shrub swamp along Milldam Creek near its confluence with the North Landing River (North Landing River Natural Area Preserve). Wax myrtle (Morella cerifera), royal fern (Osmunda spectabilis), and sawgrass (Cladium jaimacense) are abundant species here. Photo: Gary P. Fleming / © DCR Natural Heritage.