and others.
Because freshwater tidal marshes have become scarce, and since what remains supports numerous rare and threatened plant species (many of which are being displaced by invasives such as Phragmites), these habitats merit a high priority for preservation and restoration.
Scrub-shrub wetlands may occur as isolated wet thickets fed by seasonal high water tables (non-tidal situations) or in tidally-fed river bank areas along coastal waterways (e.g. Spring Creek, Cedar Creek, and the St. Jones, Murderkill and Broadkill Rivers). As the name implies, shrubs are prominent in the flora, including: buttonbush, red maple, black willow, smooth alder, marsh elder, high-tide bush, and others, the mix depending on the level of salinity influence.
Scrub-shrub wetlands help stabilize stream banks and provide cover for birds and other wildlife. Although not as strongly impacted by human activities as many other wetland habitats, certain scrub-shrub wetland subtypes (red maple/ash tidal swamps and smooth alder/silky dogwood swamps) are listed as habitats of special conservation concern in Delaware.
Atlantic White Cedar swamps can be found mainly in Sussex County, where they occur in poorly-drained, acidic, highly organic soils, either along river floodplains (including Cedar Creek, the Mispillion River and the Nanticoke River), or in the headwaters of mill ponds. They feature a white cedar tree canopy with deciduous (typically maple/gum) trees mixed in. A unique community of sphagnum moss and carnivorous plants occupies the forest floor.
Prior to extensive timbering and drainage during the 1800’s and 1900’s, white cedar swamps were abundant in Delaware, including hundreds of acres within the Great Cypress Swamp. Though now scarce in Delaware, cedar swamps provide critical habitat for certain species (sundews, pitcher plants, dragonflies, salamanders, etc.) found in few other places in the state.
Bald Cypress swamps in Delaware are the northernmost examples in the United States, and thus comprise an especially unique ecosystem to this region. Easily distinguished by the presence of the evergreen, knobby-kneed Cypress trees, these swamps can be found within forested floodplains of some southern Delaware rivers and creeks, including the James Branch near Trap Pond, Trussum Pond, the Great Swamp, and a small stand near Killens Pond.
In addition to supporting unique plant and animal communities and providing wetland benefits to the watershed, Delaware’s Bald Cypress swamps are among the most scenic and serene places to explore by canoe or kayak, with Trap Pond State Park being a prime point of entry.
Photographs courtesy of the DE Natural Heritage Program and DE Watershed Assessment Section.