4.3 Wetland Natural Communities
relatively fat valley bottoms which are not subject to fooding. Tey may vary from being permanently wet to intermittently dry and are generally fed by seepage. Tey are underlain by wet organic or mucky mineral soils, which are very acidic. Te 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. Tis tendency toward rapid succession suggests that some form of periodic or chronic nat- ural disturbance, now disrupted, may have kept the bogs open. Potential past disturbances include fooding by Beavers, grazing by herds of large mammals, fres, and clearing by Native Americans.
Tere are three community types within this ecosystem: Southern Appalachian bog, Southern Appalachian fen, and swamp forest–bog complex:
• Te Southern Appalachian bog and Southern Appalachian fen types have a mosaic or zoned pattern of shrub thickets and herb-dominated areas, mostly underlain by sphag- num mats. Trees may be scattered throughout or may dominate on the edges. Te 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; only one Southern Appalachian fen is known in North Carolina (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. Te 2005 WAP described bogs and associated wetlands (mountain bogs) as a priority habi- tat in the Southern Blue Ridge Mountains ecoregion (see Chapter 5) (NCWRC 2005) . 4.3.1.2 Location of Habitat Mountain bogs (including fens and ‘wet meadow’ bogs) are distributed throughout the Mountains and upper Piedmont of North Carolina, with examples as far east as Forsyth and Gaston Counties. Most of the known occurrences of Southern Appalachian bogs and fens are situated above the Blue Ridge escarpment, in the northwestern (Ashe and Alleghany) and southern (Henderson, Transylvania) counties. On the other hand, ‘wet meadow’ bogs can be found in the western half of the Piedmont and throughout the Mountain counties. Over 60% of the wetlands identifed in the Southern Appalachian Assessment ( SAMAB 1996 in NCWRC 2005 ) occurred on privately owned lands and it is likely that overall, the percent of mountain bog habitat in private ownership is even greater.
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2015 NC Wildlife Action Plan
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