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S-632 Natural-Heritage-Inventory-of-NHC63 New Hanover County Natural Area Inventory 421 SAND RIDGE Significant Natural Heritage Area Site significance: state Size: 7966 acres: 7071 acres within primary boundary (2029 in New Hanover County), 895 acres in secondary boundary (341 in New Hanover County) Quadrangles: Castle Hayne, Currie, Leland Ownership: New Hanover Co., private SIGNIFICANT FEATURES: 421 Sand Ridge is one of the best formed and largest of the aeolian sand ridges associated with the Coastal Plain terraces east and northeast of the Cape Fear River south from Cumberland County. Although fragmented by industrial development, primarily in New Hanover County, the site continues to support extensive natural habitat with eight community types or variants, including the rare Cypress Savanna. Ten rare plants and four rare animals have been identified from the site. Among the rare plants is the Federally and State Endangered rough-leaf loosestrife (Lysimachia asperulifolia), and four Federal Species of Concern: Sandhills milkvetch (Astragalus michauxii),Venus flytrap (Dionaea muscipula), Carolina goldenrod (Solidago pulchra), and Pickering’s dawnflower (Stylisma pickeringii var. pickeringii). Among the rare animals are the Federally and State Endangered red-cockaded woodpecker (Picoides borealis), and Federal Species of Concern southern hognose snake (Heterodon simus). LANDSCAPE RELATIONSHIPS: This site is located in northern New Hanover County and southern Pender County on the long north/south sand ridge between the lower reaches of the Northeast Cape Fear River on the east and Black River and Cape Fear River on the west. It extends southward from near Bear Branch in Pender County to just north of the confluence of Cape Fear and Northeast Cape Fear rivers in New Hanover County. Bio-geographically, it is a pivotal area connecting major ecosystems in southeastern North Carolina. It is directly connected eastward to the Northeast Cape Fear River Floodplain natural area, and from there to the Camp Lejeune/Holly Shelter Megasite extending east into Onslow County. To the west it is directly connected to the Black River Floodplain Macrosite, and from there to Bladen Lakes Natural Areas Megasite extending northward into Bladen, Sampson, and Cumberland counties. Southward it is directly connected to Brunswick River/Cape Fear River Marshes natural area in New Hanover and Brunswick counties. Within the natural area, the primary boundary includes habitat in good natural condition and/or with other exceptional biological values, while the secondary boundary includes areas of lesser natural value, but which buffer primary habitat and/or have good restoration potential. SITE DESCRIPTION: 421 Sand Ridge is characterized by rolling sandhills interspersed with numerous irregular, elliptical, and nearly round depressions, including examples of the Carolina bay geomorphic feature. The uplands support four longleaf pine ecosystem communities: Wet Pine Flatwoods Wet Spodosol Variant, and Xeric Sandhill Scrub Sand Barren, Coastal Plain, and Coastal Fringe variants. (The rare Coastal Fringe Sandhill community, formerly occurring in the southern portion of this site, has been destroyed by logging.) Dry-Mesic Oak–Hickory Forest occurs on slopes above Fishing Creek, where fire appears to have been rare naturally. Depressions that 64 intersect the water table support three wetland community types: Cypress Savanna, Small Depression Pocosin, and Vernal Pool. A few wet depressions have permanent aquatic zones and belong to the Small Depression Pond community but have been disturbed by logging, nutrient input, and other impacts. Wet Pine Flatwoods Wet Spodosol Variant occurs on wet sandy soil that tends to dry out in the latter stages of the growing season. It is found on low flats within and adjacent to sandhill habitat at 421 Sand Ridge. Longleaf pine (Pinus palustris) is the canopy dominant, with pond pine (P. serotina) locally prominent. The shrub layer is patchy to moderate, with dwarf huckleberry (Gaylussacia dumosa) dominant, and staggerbush (Lyonia mariana), inkberry (Ilex glabra), and a St. John’s-wort (Hypericum reductum) forming patches. The ground layer is moderate to moderately dense with Carolina wiregrass (Aristida stricta) dominant, creeping blueberry (Vaccinium crassifolium) subdominant to co-dominant, and the uncommon southern bogbutton (Lachnocaulon beyrichianum) locally prominent. Xeric Sandhill Scrub Sand Barren Variant occurs on the driest and most excessively drained sand ridges. The canopy is sparse to moderately open, and exclusively dominated by small longleaf pine trees typically 35-45 feet high, with the moderate to moderately dense understory dominated by small turkey oaks (Quercus laevis) 10-15 feet high. Carolina October-flower (Polygonella polygama var. croomii) is prominent in the sparse to patchy shrub layer, with Carolina wiregrass prominent in the sparse ground layer, where reindeer lichen (Cladonia sp.) forms patches. This community variant does not appear to burn frequently naturally, likely due to the sparseness of the ground vegetation. The openness of the various stratal layers is apparently due to the extreme dryness. The occurrence of this community in the New Hanover County portion of the site has been destroyed by logging, but the community persists in the Pender County portion. Dry but not as excessively drained sandhill areas support Xeric Sandhill Scrub Coastal Plain Variant, the dominant community type over much of the site. Conditions are variable, depending on soil moisture, and fire and logging history. Canopy density varies from sparse to moderately dense, with longleaf pine dominant. The oak understory is moderate to moderately dense, with turkey oak dominant. The shrub and ground layers are sparse to patchy, in some areas due to litter accumulation and increased understory density due to lack of fire, and in other areas apparently due to pinestraw raking. Dwarf huckleberry and seedling longleaf pine are patch dominants in the shrub layer, with Carolina wiregrass and little bluestem (Schizachyrium scoparium) prominent in the sparse ground layer. A small sandhill area near the southern end of the sand ridge in New Hanover County supports the uncommon Xeric Sandhill Scrub Coastal Fringe Variant community. It also occurs on very dry soil, but contains some species primarily found along the coast, such as sand live oak (Quercus geminata) and sandhill beaksedge (Rhynchospora megalocarpa). Like other sandhill sites in the region, the open to patchy canopy is dominated by longleaf pine with turkey oak forming a moderately dense to moderate understory. Sand live oak and sand laurel oak (Q. hemisphaerica) are also found in the understory. Reindeer lichen is dominant in the open to patchy ground layer, with little bluestem 65 prominent. This community contains two very rare plants, Florida scrub frostweed (Helianthemum nashii) and Pickering’s dawnflower, plus the rare southern hognose snake. Dry-Mesic Oak–Hickory Forest occurs on bluffs and slopes above the floodplain of the Northeast Cape Fear River and Fishing Creek along the east side of the site. This community type is restricted to areas naturally protected from fire by the floodplain slopes. The canopy is dominated by sand laurel oak, with mockernut hickory (Carya alba) prominent. The understory is diverse, with common pawpaw (Asimina triloba), wild olive (Osmanthus americanus), witch-hazel (Hamamelis virginiana), American holly (Ilex opaca), and farkleberry (Vaccinium arboreum) prominent. This community is bordered by Xeric Sandhill Scrub at the slope summit (where not cleared), and by marsh and swamp habitat at the slope base. A small Carolina bay in the Pender County portion of the site supports the rare Cypress Savanna community. Carolina bays are elliptical wetland basins surrounded by arcuate, usually dry sand ridges called bay rims. Cypress Savannas, especially rare on the outer Coastal Plain, occur in depressions that are shallowly flooded for much of the year, but tend to be exposed during at least the latter part of the growing season. They are characterized by an open canopy of pond-cypress (Taxodium ascendens), swamp tupelo (Nyssa biflora), and swamp red maple (Acer rubrum var. trilobum) over an herbaceous ground layer. Dominant herbs include maidencane (Panicum hemitomon), redroot (Lachnanthes caroliana), and Virginia chainfern (Woodwardia virginica). Other prominent herbs include soft-headed pipewort (Eriocaulon compressum) and witch grasses (Dichanthelium spp.). This community formerly occurred in a depression near the southern end of the site in New Hanover County, but was severely impacted by logging. Small isolated basins that intersect the water table support either the Small Depression Pocosin or Vernal Pool communities. Small Depression Pocosin occurs on saturated peats in isolated basins within the sandhill communities. It is characterized by an open canopy over a dense shrub layer. Pond pine is the canopy dominant, with fetterbush (Lyonia lucida) dominant and southern highbush blueberry (Vaccinium formosum) and staggerbush abundant. The Vernal Pool community occurs in small depressions that typically flood in winter and spring and dry out by summer. This produces ideal breeding conditions for amphibians. The seasonal pool typically is dominated by such grasses as switchcane (Panicum virgatum) and white bluestem (Andropogon capillipes). Swamp tupelo and swamp red maple are present at some pools. 421 Sand Ridge is an important wildlife area. The majority of habitat is dry sandhill with an open canopy, moderate understory, and sparse to patchy shrub and ground layers. Several small isolated depressions contain wetlands. These conditions provide home and foraging habitat for many animal species, including critical habitat for populations of the Federally and State Endangered red- cockaded woodpecker. However, extensive logging in the 1980s eliminated much habitat for this species in this area. The sandhill understory oaks provide mast for game animals, and the isolated depressions provide potential amphibian breeding sites. However, habitat has become increasingly segmented and isolated over time due primarily to industrial development, largely in New Hanover County. Such fragmentation can seriously impact several groups of animals. 66 MANAGEMENT AND PROTECTION: Natural habitat in 421 Sand Ridge has experienced a considerable reduction in recent years, especially in New Hanover County. Much habitat has been eliminated by industrial development and for county infrastructure (e.g., a 400-acre landfill). Large areas in the New Hanover County portion of the site have been logged in recent years, with considerable surface impact. Remaining habitat has become increasingly fragmented, and variously impacted by fire suppression (throughout) and pinestraw raking (local). Portions of remnant native ground layers in powerline corridors have been replaced by large food plots. The US 17 Wilmington Bypass is scheduled to cross this site, adding to the reduction and fragmentation of remaining natural habitat. Management efforts should focus on restoring natural processes such as fire, while protection efforts should seek to preserve large areas of intact or easily restorable natural habitat. NATURAL COMMUNITIES: Cypress Savanna*, Dry-Mesic Oak–Hickory Forest, Small Depression Pocosin*, Vernal Pool, Wet Pine Flatwoods Wet Spodosol Variant, Xeric Sandhill Scrub Coastal Fringe Variant, Xeric Sandhill Scrub Coastal Plain Variant, Xeric Sandhill Scrub Sand Barren Variant*. RARE PLANTS: Sandhills milkvetch (Astragalus michauxii), Venus flytrap (Dionaea muscipula)*, Robbin’s spikerush (Eleocharis robbinsii), Florida scrub frostweed (Helianthemum nashii), roughleaf loosestrife (Lysimachia asperulifolia)*, shrubby seedbox (Ludwigia suffruticosa), West Indies meadow-beauty (Rhexia cubensis), lace-lip ladies’-tresses (Spiranthes laciniata), Carolina goldenrod (Solidago pulchra)*, Pickering’s dawnflower (Stylisma pickeringii var. pickeringii). RARE ANIMALS: southern hognose snake (Heterodon simus), coachwhip (Masticophis flagellum), red-cockaded woodpecker (Picoides borealis), eastern fox squirrel (Sciurus niger). *Only in Pender County at this site REFERENCES: DuMond, D.M. 1977. Rare plant survey: proposed Northeast Cape Fear River disposal sites. Wilmington District Corps of Engineers, Wilmington, N.C. LeBlond, R.J. 1999. Site survey report: 421 Sand Ridge, Takeda survey site. N.C. Natural Heritage Program, OCCA, DENR, Raleigh, NC. LeBlond, R.J. 2000. Natural Area Inventory of Pender County, North Carolina. N.C. Natural Heritage Program, OCCA, DENR, Raleigh, N.C. Leonard, S.W., and R.J. Davis. 1981. Natural area inventory of 421 Sand Ridge. In Natural Areas Inventory of Pender County, North Carolina, pp. 106-118. Coastal Energy Impact Program (CEIP) Report No. 11, N.C. Coastal Management Program. Schafale, M., A. Weakley, H. LeGrand, and S. Hall. 1993. Natural Heritage site survey report: 421 Sand Ridge, southern portion. N.C. Natural Heritage Program, Office of Conservation and Community Affairs, DENR, Raleigh, N.C.