Habitats of North Carolina
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General Shrublands
General Corylaceous Thickets and Understories
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General Description The key factor for this habitat is the presence of hornbeams, hop-hornbeams, or hazelnuts, members of the former family Corylaceae and now a subfamily within the Betulaceae. These species are shrubs and occasionally subcanopy species within hardwood forests. Habitat conditions range from wet bottomlands and swamp margins -- including Blackwater as well as Brownwater examples -- occupied by American Hornbeam, to rich mesic forests occupied by American Hazelnut and American Hop-Hornbeam, to dry-xeric rocky forests occupied by Beaked Hazelnut.

The ranges of these plants are more restricted than the habitat as a whole and they are consequently treated only as habitat factors, not the Determining Species of this habitat. The insect herbivores that specialize on this plant group, on the other hand, do make use of the entire range occupied by this group and are consequently considered Determining of this particular habitat. MOst of these species have been documented to feed on two or more of the plant species of the "Corylaceae". They do not, however, feed at least regularly on either birches or alders, the other main genera of the Betulaceae.

Abiotic Factors Geographic Regions: Lower Coastal Plain to High Mountains. USDA Hardiness Zones: 6-8. Landform: ridges, slopes, bottomlands, and wet flats. Slope Aspect: occurs on all slopes aspects as well as on ridges and flats. Soil Moisture: Dry to wet. Soil texture: loamy to alluvial. Soil pH: circumneutral to acidic. Soil Nutrient Content: poor in the blackwater floodplains occupied by American Hornbeam but rich in mafic or calcareous minerals in slopes occupied by Hop-hornbeam and the Hazelnut species. Microclimate: Warm to cool, dry to humid. Hydrological Features: springs and seeps are common, particularly at the interface between slopes and bottomlands. Flood Frequency: the bottomlands occupied by American Hornbeam may flood several times per year; the ridges and upper slopes occupied by Hop-hornbeam and Hazelnuts rare flood, if ever . Flood Duration: hours to days in the bottomlands and lower slopes. Fire Frequency: occasional on ridges and upper slopes, rare in bottomlands Drought Frequency: occasional on upper slopes, rare in bottomlands. Ice Storm Damage: low to moderate. Wind Storm Damage: moderate. Insolation: the shrub layers belonging to this habitat are generally deeply shaded.

Biotic Structure Key Species: Corylus, Carpinus, or Ostrya species must be present. Vegetation Type: closed-canopy forest composed of broadleaf, deciduous trees. Strata: subcanopy and shrub layers are well developed. Shelter: Woody debris and leaf litter are usually plentiful.

Co-evolved Species Groups Phagic and Competitory Symbioses:
Carpinus-Corylus-Ostrya // Acronicta laetifica-Baileya ophthalmica-Caloptilia ostryaeella-Cameraria ostryarella-Coleophora ostryae-Ectoedemia quadrinotata-Hypena palparia-Pyreferra citrombra-Zale phaeocapna
Corylus species // Cameraria corylisella-Olethreutes corylana-Phyllonorycter intermixta
Ostrya virginiana // Acrobasis sylviella

Determining Species
Taxa Global RankState RankProbability of Extirpation (PE)
Acrobasis normella GNRSU0.0020
Acrobasis sylviella - Ironwood Tubemaker Moth GNRS2S30.0164
Acronicta laetifica - Pleasant Dagger G5S40.0007
Baileya ophthalmica - Eyed Baileya G5S4S50.0002
Caloptilia ostryaeella GNRSU0.0020
Cameraria corylisella GNRSU0.0020
Cameraria ostryarella GNRSU0.0020
Coleophora ostryae GNRSU0.0020
Ectoedemia quadrinotata GNRSU0.0020
Hypena palparia - Mottled Bomolocha G5S4S50.0002
Olethreutes corylana GNRS3S40.0020
Phyllonorycter intermixta GNRS2S40.0058
Pyreferra citrombra - Citrine Sallow GNRS2S30.0164
Zale phaeocapna - Phaeocapna Zale G5S3S40.0020
Expected Number of Extirpations with a PE value (Sum of PE) = 0.0557
N = Number of Extant Species with a PE value = 14
Average PE = ENE/N = 0.0040
Number of S5 species = 0
Proportion of Secure Species = Number of S5 Species/N = 0.0000
Habitat Risk Index = ENE x (1 – PSS) = 0.0557

Estimated Risk to the Determining Species
Estimated Security of the Habitat
Index of Habitat Imperilment
Identified Risks
Observed Trends
Distribution Map
Major Conservation Reserves
Priority Areas for Surveys and Conservation Protection
Stewardship and Management Recommendations
Updated on 2022-01-02 14:32:06