Chapter 4 Habitats
4.3.2 Bogs and Fens 4.3.2.1 Ecosystem Description
Mountain and Piedmont bogs are among the rarest natural communities in the Southern Appalachians and in North Carolina. Unlike northern bogs of glacial origin, Southern Appalachian bogs form in poorly drained depressions or on gentle slopes, generally in relatively flat valley bottoms that are not subject to flooding. They may vary from being permanently wet to intermittently dry and are generally fed by seepage. They are underlain by wet organic or mucky mineral soils, which are very acidic. The factors responsible for creating and maintaining bog communities are not well known. Grazing has been nearly universal in bogs, and few examples exist in pristine condition. Most are experiencing invasion of shrubs or trees at the expense of the herbaceous zones. This tendency toward rapid succession suggests that some form of periodic or chronic natural disturbance, now disrupted, may have kept the bogs open. Potential past disturbances include flooding by Beavers, grazing by herds of large mammals, fires, and clearing by Native Americans.
Classification of the Natural Communities of North Carolina, Fourth Approximation (Schafale 2012, 2024) notes there are several subtypes for this community.
• Swamp Forest-Bog Complex (Typic, Spruce subtypes) • Southern Appalachian Bog (Typic, Low Elevation, Long Hope Valley, Skunk Cabbage subtypes) • French Broad Valley Bog • Low Mountain Seepage Bog • Southern Appalachian Fen (Bluff Mountain, Glades subtypes) The Southern Appalachian bog and Southern Appalachian fen subtypes have a mosaic or zoned pattern of shrub thickets and herb-dominated areas, mostly underlain by sphagnum mats. Trees may be scattered throughout or may dominate on the edges. The shrub and herb layers of the bog, while not highly diverse, are uniquely adapted to the acidic, nutrient-poor environment of the bog and may include numerous rare species. Fens occur on high pH (basic) soils but otherwise have the same vegetative zones as bogs. Southern Appalachian fen subtypes are known in North Carolina only at Bluff Mountain and The Glades (in Ashe County). Swamp forest-bog complex types occur along streams and are dominated by trees but may have boggy herbs and sphagnum moss in canopy openings. They generally occur at elevations above 3,500 feet.
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2025 NC Wildlife Action Plan
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