other counties in North Carolina, as is Potomogeton foliosus 

 (Leafy pondweed) . Both these are found here around submerged 

 tree stumps in the lower pond. As species they seem to require 

 very clean, unpolluted water, which may explain their confinement 

 to the area of the pond closest to the spillway. 



Sediments and pollutants entering the pond appear to be 

 strained out and deposited in the upper reaches. Originating as 

 agricultural runoff, these materials pass through Lassiter Swamp 

 and enter the upper pond, where still water and a thick growth of 

 aquatic plants remove them from suspension and solution. A series 

 of conductivity readings taken in fall, 1976 showed that the 

 total amount of dissolved material decreased regularly from the 

 upper pond to the lower end near the spillway. 



Neither species is common here, and their limitation to the 

 cleanest waters of the pond indicate that their presence is 

 endangered at this site. Additional runoff of sediment and 

 nutrients from fertilizer and livestock wastes would probably 

 eliminate these species from the county flora. 



Wolf f ia papulifera (Pappilose water meal) occurs in the 

 pond but is rare in some years. Wolf f ia columbiana was listed for 

 the site in the park master plan but only the above species has 

 been seen during the past six years. An unidentified species of 

 Ludwigia, which could be a state record, also occurs at the pond. 



CT-D. BLACK GUM SWAMP ( Nyssa sylvatica biflora/Acer rubrum-Liriodendron 

 tulip if era-Liquidambar styraciflua /mixed mesophytic herbs) . 



This community type is best seen on the recently purchased 

 Cathleen Edwards tract along a small swamp tributary leading 

 from SR 1404 into the southeastern headwaters of the mill pond. 

 This is the type, within the natural area, which most closely 

 resembles the dominant community of the Dismal Swamp. The 

 presence of yellow poplar and sweet gum is probably due to the 

 presence of colluvium along the valley borders and could likely 

 be segregated as a distinct community type. 



This community type contains two rare herb species plus a 

 third, Listera australis (Southern twayblade) on the adjacent 

 uplands. The four other sites for this orchid species in the 

 county are on low moist sands around the periphery of sand 

 ridges in swamps. Here it occurs at an elevation of 35 ft in a 

 pine successional area. Its presence on this atypical site may 

 be due to a local seepage area. 



' Yellow water crowfoot ( Ranunculus flabellaris ) is found 



at the lowest elevation on this site, along the tributary swamp 

 and is actually confluent with the larger population of this 

 species described under CT-B (Tupelo Swamp) . Along the eastern 



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