This community is typical of many pond pine-evergreen 

 shrub associations overlying deep peat areas in the eastern 

 coastal plain of North Carolina. They are quite distinct, 

 both structurally and f loristically , from swamp forests 

 which are usually dominated by combinations of swamp black- 

 gum, cypress, and Atlantic white cedar. Vegetation of the 

 evergreen shrub bogs or pocosins have been described else- 

 where in the literature (Kologiski , 1977; Wells, 1942; Wells, 

 1967) . Most botanists agree that the evergreen shrub bogs or 

 pocosins are 1) usually over moderate to deep peat layers; 



2) have seasonal high water tables at or near the surface; 



3) are almost always associated with non-alluvial, upland 

 basins and interstream divides; 4) mostly are the result 

 of blocked drainages with the major exception of Carolina 

 bays, and 5) are dominated by a diversity of fire resistant 

 woody shrubs and usually containing at least a few scattered 

 pond pines. 



The Van Swamp pond pine pocosin appears to be highly 

 correlated with a particular soil series, Pungo muck (dysic, 

 thermic Typic Medisaprists) . This peat soil is characterized 

 by upper organic horizons from 51 to more than 90 inches thick 

 underlain by clayey mineral horizons. The seasonal water table 

 is at or near the surface throughout much of the year. These 

 soils differ from Belhaven muck in having much thicker organic 

 layers (4-10 feet in depth) . Recently, Otte (1981) has described 

 a number of interrelated processes which he believes account for 

 the distribution of pond pine pocosin in the peat dominated wet- 

 lands of the coastal plain. He concludes that an important 

 factor concerning the maintenance of pocosins is direction of 

 water flow. 



"Swamp forest peat (based on a number of samples) 

 contains a higher average mineral content than 

 does pocosin peat. This sediment is carried into 

 the wetlands by surface runoff from the surrounding 

 uplands. This runoff most likely also carries dis- 

 solved nutrients that would not be available to a 

 system fed primarily by precipitation (i.e., pocosins) ." 



He contends that if surface runoff from adjacent highlands flows 

 part-way into a peat-dominated wetland, but not all the way 

 through, the outer margins of the wetland most likely would 

 develop into swamp forest and the sediment-free, nutrient- 

 deprived inner portions would likely develop pocosin vegetation. 



In Van Swamp the distribution of the pond pine pocosin 

 seems to support this hypothesis. The pocosin vegetation 

 occurs in a zone of very deep peat (mapped as Pungo muck) 

 located in the east-central portion of the swamp. Shallower 

 peat areas on either side of the pocosin are dominated by 



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