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Environmental Assessment for EFH ACE Basin NWR Hunting Plan Amendment (Youth
turkey hunting)
boundaries are established along geographic features that can be easily identified on the ground (e.g.,
rivers, roads, trails).
The refuge is drained by two significant river systems: the Combahee-Salkahatchie, which flows through
the Combahee unit, and the South Edisto, which flows adjacent to the Edisto unit. Many broad, low-
gradient interior drains are present as either extensions of tidal streams and rivers or flooded bays and
swales. The refuge's mean tidal amplitude ranges from around 2 feet on the upper reaches of the
Combahee River to 5 feet on the lower refuge area along the South Edisto River. Salinities range from
fresh water in the upper reaches to 6-7 ppt on the lower reaches, with season deviations occurring
depending on precipitation amounts. The major vegetative communities on the refuge include natural
marshes, managed marshes (wetland management units), forested wetlands, and upland forest. General
characteristics of each community and associated wildlife are as follows:
Natural Marshes
Dominant plants in freshwater marshes include giant cutgrass, common cattail, northern wild rice,
pickerel weed, arrowheads, smartweeds, various rushes, spikerushes, and sedges. Brackish marshes are
dominated by big cordgrass, narrow-leaved cattail, tropical cattail, black needlerush, and saltmarsh
bulrush, together with soft-stem, American and Olney bulrushes.
Managed Marshes (Wetland Management Units)
Management of naturally occurring plant communities within these wetland management units provides
cover and food resources required to meet the behavioral and nutritional needs of waterfowl, as well as a
broad spectrum of other wildlife species. In freshwater units managed by spring and summer drawdown,
waterfowl food plants include wild millets, panic grasses, smartweeds, and flat sedges. In freshwater units
managed as semi-permanently flooded marshes, waterfowl food or cover plants include watershield,
white waterlily, and pondweeds. Important waterfowl food plants encouraged in brackish units include
widgeongrass, saltmarsh bulrush, and dwarf spikerush.
Grasslands
Grasslands occur primarily in the Grove and Bonny Hall sub-units, with the Grove containing the
majority in the form of previously farmed pastureland that has been managed to support naturally
occurring warm-season grasses. Species composition in these grasslands typically include broomsedge,
big bluestem, switchgrass, foxtail grass, giant plumegrass, vasey grass, and eastern gamma grass.
Forested Wetlands
Forested wetlands occur primarily in the upper portion of the floodplains of the Combahee unit. The
cypress-tupelo swamp forest occupies deep sloughs, margins of oxbows, and wet flats, and is flooded for
at least some portion of the year. Dominant vegetation includes bald cypress, water tupelo, swamp tupelo,
green ash, red maple, wax myrtle, and titi. The bottomland hardwood forest type is drier than the cypress-
tupelo forest and is inundated for a considerably shorter period. This forest type supports water oak, laurel
oak, overcup oak, water hickory, sweet gum, and green ash, along with a scattering of pond pine, spruce
pine, loblolly pine, and cypress.
Upland Forest
The primary vegetative types are pine and pine-hardwood. Past logging and agricultural practices,
combined with present day forestry management, has resulted in monotypic loblolly pine plantations in
many areas. Pine-hardwood forests are relatively common and occur on both wet and dry sites. Wet areas