Habitats of North Carolina
Habitat Group:
Habitat Type:
Members of Marshes, Mires, and Shoreline Habitats:
« »
Marshes, Mires, and Shoreline Habitats
General Broadleaf Herbaceous Mires
General Description This habitat includes the entire range of shallow, mucky wetlands that support dense growths of wetland forbs. These can occur as open marshes, bogs, and fens or as seeps and shallow pools in closed canopy forests. Examples occur over a broad climatic range and are widely distributed across the state.

Determining Species include both ferns and forbs. Mire habitats dominated by sedges and other Graminoids are treated in other habitats, as are those that are restricted to either the Mountains or Coastal Plain. Animal species consist of herbivores that are specialized on the plant members of this habitat.

Abiotic Factors Geographic Regions: High Mountins to the Lower Coastal Plain. USDA Hardiness Zones: 6-8. Landform: restricted to floodplains and wet flats. Soil Moisture: hydric. Soil Texture: mucky. Soil pH: usually acidic due to the build-up of humic acids. Soil Nutrients: generally poor with nutrient-rich examples found only in a few fens. Mucky soils are also typically anoxic. Microclimate: warm to cool, humid. Flood Frequency: several times per year to permanent. Flood Duration: weeks to months or permanent. Presence of Pools: mires are only shallowly flooded although pools may be located close by. Fire Frequency: uncommon in bottomlands but frequent when adjoining fire-maintained habitats. Drought Frequency: rare. Insolation: partial to full sun.

Biotic Structure Vegetation Type: forbland: species of aquatic forbs are the dominant plant species in this habitat; graminoids may also be present, but occur only as scattered individuals or small patches. Strata: canopy, subcanopy, and shrub layers can be well-developed or absent. Woody Debris and Leaf Litter: logs and fallen branches may be present where these mires occur within forests but may be otherwise absent

Co-evolved Species Groups Phagic and Competitory Symbioses:
Boehmeria cylindrica // Hypena manalis
Pilea pumila // Cosmopterix pulchrimella-Heterophleps triguttaria
Onoclea sensibilis // Papaipema inquaesita
Osmunda spectabilis-Osmundastrum cinnamomeum // Papaipema speciosissima
Pontederia cordata // Bellura densa
Saururus cernuus // Parapamea buffaloensis

Determining Species
Odontota scapularisOrange-shouldered Leaf MinerSNR
Onoclea sensibilisSensitive FernG5S5S50.00000
Osmunda spectabilisAmerican Royal FernG5S5S50.00000
Thelypteris palustrisMarsh FernG5S5S50.00000
Chelone obliquaRed TurtleheadG4S2S20.03699
Nelumbo luteaAmerican Lotus-lily, Yellow Lotus, YockernutG4S2S20.03699
Platanthera peramoenaPurple Fringeless OrchidG5S2S20.03699
Stachys asperaRough Hedge-nettleG4S2S20.03699
Alisma subcordatumBroad-leaved Water-plantainG5S3S30.00407
Chelone cuthbertiiCuthbert's TurtleheadG3S3S30.00407
Lobelia georgianaGeorgia LobeliaGNRS3S30.00407
Platanthera flavaSouthern Rein-orchidG4S3S30.00407
Platanthera laceraGreen-fringe OrchisG5S3S30.00407
Symplocarpus foetidusSkunk CabbageG5S3S30.00407
Chelone glabraWhite TurtleheadG5S3S4S3S40.00132
Sagittaria australisLongbeak ArrowheadG5S3S4S3S40.00132
Mimulus alatusSharp-wing MonkeyflowerG5S4S40.00041
Platanthera clavellataSmall Green Woodland OrchidG5S4S40.00041
Pluchea camphorataMarsh FleabaneG5S4S40.00041
Scutellaria laterifloraMad Dog SkullcapG5S4S40.00041
Viola cucullataMarsh Blue VioletG5S4S40.00041
Boehmeria cylindricaFalse NettleG5S5S50.00000
Impatiens capensisSpotted Jewel-weedG5S5S50.00000
Lobelia cardinalisCardinal FlowerG5S5S50.00000
Peltandra virginicaGreen Arrow-arumG5S5S50.00000
Pilea pumilaCanada ClearweedG5S5S50.00000
Pontederia cordataPickerel WeedG5S5S50.00000
Sagittaria latifoliaBroadleaf ArrowheadG5S5S50.00000
Saururus cernuusLizard's TailG5S5S50.00000
Sparganium americanumAmerican Bur-reedG5S5S50.00000
Hypericum adpressumBog St. John's-wortG3SHSH
Cosmopterix pulchrimellaChambers' Cosmopterix Moth, Beautiful Cosmopterix MothGNRSUS1S30.03699
Pristerognatha agilanaGNRSUS2S40.00407
Papaipema inquaesitaAster Borer, Sensitive Fern Borer MothG5S3S4S3S40.00132
Papaipema speciosissimaOsmunda Borer MothG4S3S4S3S40.00132
Parapamea buffaloensisBuffalo MothG4S4S40.00041
Bellura densaPicklerelweed Borer MothG5S4S5S4S50.00010
Heterophleps triguttariaThree-spotted FillipG5S4S5S4S50.00010
Hypena manalisFlowing-line HypenaG5S4S5S4S50.00010
Apios americanaAmerican GroundnutG5S4S40.00041
Nr = Number of Ranked Species = 39
Ner = Number of Extant, Ranked Species = 38
Nv = Number of Historic and Extirpated Species = 1
Nar = Number of Species at Risk of Extirpation (State rank > S5) = 26
Nss = Number of Secure Species (State Rank = S5) = 12
Pss = Proportion of Secure Species (Nss/Ner) = 0.31579
ENE = Expected Number of Extirpations (Sum of PE) = 0.22189
Average PE (ENE/Ner) = 0.00584
Habitat Risk Index = (Nar+Nv) x Average PE = 27 x 0.00584 = 0.15768

Estimated Risk to the Determining Species No S1 species have been identified as Determining Species of this habitat but there are four that are ranked as S2. One additional species, Creeping St. Johns Wort, is considered Historic and probably extirpated from the state. The reasons why this species has disappeared despite the relative commonness of its habitat appear to be unknown.

The Average Probability of Extirpation is the equivalent of a State Rank of S3, indicating a moderate degree of conservation concern.

Estimated Risk to the Co-evolved Species Groups
Estimated Security of the Habitat Twelve of the Determining Species are considered Secure within the state and the Proportion of Secure Species is 32%. This reflects the fact that this habitat is widely distributed across the state. Although rarely occurring as single, very large blocks, the location of these habitats along riparian corridors usually provides a high degree of connectivity.

Index of Habitat Imperilment This habitat has a moderate number of Species at Risk, which coupled with the moderately low value for Average PE produces a moderate value for the Expected Number of Extirpations. In calculating the value for HRI, the combination of the low ENE and moderately high PSS results in a fairly low value, but this is raised somewhat by factoring in the one historic species. This value falls within our Tier 4 Level of Conservation Concern (0.05 ≥ HRI > 0.005).
Identified Risks This habitat is vulnerable to impacts of human activities that affect wetlands more generally. These included habitat conversion involving the filling and/or drainage of specific sites, runoff of sediment- and pollutant-laden stormwaters from development of nearby uplands, construction of reservoirs, and invasion by exotic species.

Observed Trends Loss of mire habitats, especially in the inland portions of the state, has generally not been adequately recorded or estimated.

Distribution Map
Distribution The map shows the wide distribution of this somewhat generalized habitat. The fact that few counties display the maximum number of species is probably mainly due to incomplete survey coverage. This is particularly true for the Insect members of this habitat, with most of the counties represented solely by plant species.
Major Conservation Reserves
Priority Areas for Surveys and Conservation Protection
Stewardship and Management Recommendations Wetland conservation is considered valuable for a number of reasons, including the protection of water quality for human uses and for flood control; a large number of federal and state programs exist particularly for that purpose and that are largely oriented towards the restoration of degraded wetlands. Plugging drainage ditches to restore natural hydrology is one important type of management, as is the reduction of tree cover in some cases in order to counteract the effects of transpiration. For the conservation of the native biodiversity of wetlands, particularly the small, naturally isolated types that are included within this habitat, protection of existing, high quality occurrences needs to be given much more emphasis than it currently receives. Given the patchy nature of the distribution of these habitats, attention also importantly needs to be given to maintaining the connections -- usually riparian corridors -- that link them together. A system of interacting, mutually reinforcing units is critical for the long-term persistence of these habitats.

Updated on 2022-06-14 11:58:38