Habitats of North Carolina
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Conifer Forests
White Cedar Forests
General Description The defining feature of this habitat is the presence of Alantic White Cedars (Chamaecyparis thyoides), which grows solely on acidic, nutrient-poor peatland soils in the Coastal Plain. The water table is high in the wetlands occupied by this species, and the soils are constantly saturated but rarely deeply flooded. The largest stands of Atlantic White Cedar occur as non-riverine swamp forests in the Outer Coastal Plain (Schafale, 2012). Smaller, but numerous, expanses of the cedars also occur in association with Carolina Bays and in pond and streamhead communities in the Fall-line Sandhills. Other stands are located along the terraces of blackwater rivers.

White Cedars are relatively shade-intolerant and will succeed to Bay Forests or Pond Pine Woodland if left undisturbed (Tirmenstein, 1991). While the cedars are killed in fires or large blowdowns produced by hurricanes, such disturbances are necessary to regenerate the stands and to keep competing hardwood vegetation at bay. To be beneficial, however, fires cannot be so intense as to burn into the peat layers where the seeds of the cedars accumulate; fires that burn into the peat often leave only ponds behind with little, if any, chance of recovery by the cedars.

White Cedar Forests typically have dense and diverse shrub layers composed of species associated with wet, acidic, organic soils, but none are known to show a particularly high fidelity to the White Cedars Forests themselves. The same is true for vertebrate animals. The density of breeding birds can be quite high within stands of White Cedar compared to adjoining stands of swamp hardwoods (Terwilliger and Rose, 1987) but again, none show any great restriction to this habitat type. The coastal populations of Black-throated Green Black-throated Green Warbler (Setophaga virens waynei), come close, however, preferentially nesting in non-riverine swamp forests that contain a mixture of conifers -- including Bald Cypress as well as White Cedar -- and hardwoods (LeGrand et al., 2019).

Most of the insect species that feed on White Cedars also feed on other members of the Cupressaceae and are included in the more general Cedar Woodlands habitat. Two species, however, are believed to be restricted to Chamaecyparais thyoides: Hessel's Hairstreak Callophrys hesseli and Brenda's Hypagyrtis Moth Hypagyrtis brendae. Hessel's Hairstreak (Callophrys hesseli) was described as a distinct species from C. gryneus in 1950 by Rawson and Ziegler (1950), who also recognized its host plant to be Chamaecyparis thyoides. Brenda's Hypagyrtis (Hypagyrtis brendae) was originally described by Heitzman from the Ohio Valley, where Atlantic White Cedar does not occur. The first East Coast population was discovered by S. Hall in 1994 (see Fussell et al., 1995). Although larvae have not yet been observed, nearly all observations of this species in North Carolina have been made in stands of Atlantic White Cedar, with only a single individual found near the mouth of a tidal creek not directly observed in association with that species. Our form of this moth probably represents an undescribed species.

Abiotic Factors
Biotic Structure
Co-evolved Species Groups Phagic and Competitory Symbioses:
Chamaecyparis thyoides // Callophrys hesseli-Hypagyrtis brendae


Determining Species
Taxa Global RankState RankProbability of Extirpation (PE)
BUTTERFLIES
Callophrys hesseli - Hessel's Hairstreak G3S30.0058
CONIFERS
Chamaecyparis thyoides - Atlantic White Cedar G4S30.0058
MOTHS
Hypagyrtis brendae - Brenda's Hypagyrtis Moth G4S2S30.0164
Expected Number of Extirpations with a PE value (Sum of PE) = 0.0280
N = Number of Extant Species with a PE value = 3
Average PE = ENE/N = 0.0093
Number of S5 species = 0
Proportion of Secure Species = Number of S5 Species/N = 0.0000
Habitat Risk Index = ENE x (1 – PSS) = 0.0280

Estimated Risk to the Determining Species
Estimated Security of the Habitat
Index of Habitat Imperilment
Identified Risks
Observed Trends
Distribution Map
Distribution
Major Conservation Reserves
Priority Areas for Surveys and Conservation Protection
Stewardship and Management Recommendations
References Fussell, J.O.; Webster, W.D.; Hall, S.P.; LeGrand, H.E.; Schafale, M.P.; and Russo, M.J. 1995. Ecosystem survey of Dare County Air Force Range, North Carolina. Rep. to N.C. Natural Heritage Program, Division of Parks and Recreation, Department of Environment and Natural Resources; Raleigh, NC

LeGrand, H.E., J. Haire, N. Swick, and T. Howard. 2019. Birds of North Carolina Website. Accessible at: http://ncbirds.carolinabirdclub.org/

NCFS. Accessed 2019. Atlantic White Cedar. Accessible at: https://www.ncforestservice.gov/Managing_your_forest/atlantic_white_cedar.htm

Rawson, G.W. and Ziegler, J.B., 1950. A new species of Mitoura Scudder from the pine barrens of New Jersey (Lepidoptera, Lycaenidae). Journal of the New York Entomological Society 58:69-82

Terwilliger, K. and R.K. Rose. 1987. Breeding birds of two Atlantic white cedar (Chamaecyparis thyoides) stands in the Great Dismal Swamp. In: Laderman, Aimlee D., ed. Atlantic white cedar wetlands. Westview Press: 215-227. Accessible at: https://sora.unm.edu/sites/default/files/journals/nab/v038n01/p00024-p00027.pdf

Tirmenstein, D. A. 1991. Chamaecyparis thyoides. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/tree/chathy/all.html [2019, July 9]

Vaughan, D. M., and M. D. Shepherd. 2005. Species Profile: Mitoura hesseli. In Shepherd, M. D., D. M. Vaughan, and S. H. Black (Eds). Red List of Pollinator Insects of North America. CD-ROM Version 1 (May 2005). Portland, OR: The Xerces Society for Invertebrate Conservation. Accessible at: https://xerces.org/hessels-hairstreak/

Updated on 2022-01-01 00:26:12