Habitats of North Carolina
Habitat Group:
Habitat Type:
   
Members of Peatland Forests and Shrublands:
« »
Peatland Forests and Shrublands
Mountain Bogs
General Description Mountain Bogs are open, herb-dominated peatlands and -- as we define them -- have Determining Species that are restricted to the Mountains. Some also occur in mountain fens but species that show high fidelity to circumneutral, nutrient-rich fens are treated separately.

In addition to adaptations for dealing with the saturated, acidic, nutrient-poor, and often anoxic conditions typical of peatlands, the Determining Species of this habitat are herbaceous plants that require open, sunny conditions. The lack of tree cover in these habitats is not completely understood, but may the result of past beaver activity, grazing, or fire. Paludification, which is the build-up and spread of sphagnum -- a major factor in boreal habitats where there is a net input of water vs. output -- has also been suggested (see Weakley and Schafale, 1994).

The plant species included as Determining Species are all highly restricted. One species, the Appalachian Yellow Asphodel has, in fact, been declared extinct and the Lesser Bladderwort is known only historically in North Carolina. Nine others are state ranked as S1 and the most secure species is listed as S2. The majority are disjunct from their primarily northern distributions and probably represent Pleistocene relicts. The Yellow Mountain Asphodel, although endemic to the Southern Appalachians, may also belong to this group, since its closest relative,Narthecium americanum, is a northern species. The two pitcher plants, on the other hand, have a Southeastern origin, with the Mountain Sweet Pitcherplant being narrowly endemic to the Southern Appalachians (see Weakley and Schafale, 1994, for a review of the biogeographic patterns shown by these species).

The rarity of these species may be largely due to the major changes in climate that have occurred since the last Ice Age and to more recent changes, such as the extirpation of beaver or the utilization of nearly all level ground in the mountains for cultivation or pasturage. However, the small size and high degree of isolation that is typical of these habitats is also likely to be a major contributor: when a population of any one of these species is locally extirpated, there is an decreasing chance that it will recover due to dispersal from some other nearby occurrence of this habitat.

This factor appears to be significant for the plant members of this habitat but it may be especially important in explaining the essential absence of any animals that are strongly associated with them. Although there are several species, such as Bog Turtles and Pitcher Plant Moths (Exyra semicrocea) that have been recorded in North Carolina mountain bogs, these species are associated with peatlands more generally and do not show the high fidelity to Mountain Bogs as such that is needed to describe them as Determining Species of this habitat. Even those species, moreover, appear to have difficulties maintaining their populations in mountain bogs. A population of Exyra semicrocea, a symbiont of several species of Pitcher Plants, was documented at just a single North Carolina Mountain Bog in the 1990s but is now thought to be extirpated from that site. While more surveys, covering a wider range of peatland habitats in the mountains needs to be done, it is also possible that this species has become completely eliminated from this region of the state (see discussion of survey needs under the General Herbaceous Peatlands habitat).

Abiotic Factors
Biotic Structure
Co-evolved Species Groups
Determining Species
sciNamecomNameg_ranks_rankmod_s_rankprob_of_extirpation
CLUBMOSSES
Lycopodiella inundataBog ClubmossG5S1S10.33330
FERNS
Coryphopteris simulataBog FernG4G5S1S10.33330
FORBS
Arethusa bulbosaBog RoseG5S1S10.33330
Menyanthes trifoliataBuckbeanG5S1S10.33330
Myrica galeSweet GaleG5S1S10.33330
Sarracenia jonesii Mountain Sweet Pitcher PlantG2S1S10.33330
Sarracenia oreophilaGreen Pitcher PlantG2S1S10.33330
Campanula aparinoidesMarsh BellflowerG5S2S20.03699
Helonias bullataSwamp PinkG3S2S20.03699
Utricularia minorSmall BladderwortG5SHSH
Narthecium montanumAppalachian Yellow AsphodelGXSXSX
GRAMINOIDS
Anthoxanthum hirtumG5S1S10.33330
Carex utriculataBeaked SedgeG5S1S10.33330
Nr = Number of Ranked Species = 13
Ner = Number of Extant, Ranked Species = 11
Nv = Number of Historic and Extirpated Species = 2
Nar = Number of Species at Risk of Extirpation (State rank > S5) = 11
Nss = Number of Secure Species (State Rank = S5) = 0
Pss = Proportion of Secure Species (Nss/Ner) = 0.00000
ENE = Expected Number of Extirpations (Sum of PE) = 3.07368
Average PE (ENE/Ner) = 0.27943
Habitat Risk Index = (Nar+Nv) x Average PE = 13 x 0.27943 = 3.63259

Estimated Risk to the Determining Species
Estimated Risk to the Co-evolved Species Groups
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 Murdock, N.A., 1994. Rare and endangered plants and animals of southern Appalachian wetlands. In Wetlands of the Interior Southeastern United States (pp. 189-209). Springer, Dordrecht.

Weakley, A.S., and M.P. Schafale. 1994. Non-alluvial wetlands of the southern Blue Ridge: diversity in a threatened ecosystem. Water, Air and Soil Pollution 77: 359-383. Available online at: https://www.researchgate.net/profile/Alan_Weakley/publication/226417936_Non-Alluvial_Wetlands_of_the_Southern_Blue_Ridge_-_Diversity_in_a_Threatened_Ecosystem/links/02e7e5249acd114f50000000/Non-Alluvial-Wetlands-of-the-Southern-Blue-Ridge-Diversity-in-a-Threatened-Ecosystem.pdf

Wichmann, B.L., 2009. Vegetation of Geographically Isolated Montane Non-alluvial Wetlands of the Southern Blue Ridge of North Carolina. Masters Thesis, NC State University. Available online at:: https://repository.lib.ncsu.edu/bitstream/handle/1840.16/661/etd.pdf?sequence=1&isAllowed=y
Updated on 2020-11-25 14:08:28