VI. ECOLOGY OF THE FRF SITE 



The mid-1600 settlement of the Outer Banks drastically changed the vege- 

 tation and topography of the region. Forests were diminished for fuel and 

 building, and grass and shrubs were uprooted by grazing livestock which con- 

 tinued into the beginning of the 1900' s. Once vegetation was disrupted the 

 sandy soils became susceptible to movement by wind and storm tides. The 

 blowouts and sand dunes seen today are results of these forces. 



In 1935 the Works Progress Administration and the Civilian Conservation 

 Corps began stabilizing the foredune from the Virginia border to approximately 

 the middle of Ocracoke Island. Some of these foredunes now exceed 8 meters in 

 height. The ocean beach, foredunes, arborescent (tree- and shrub-dominated) 

 and sound-side marsh zones are the most characteristic features of the Outer 

 Banks profile (Levy, 1976). The most variable zone is between the foredune 

 and the arborescent zone. This is particularly evident at the FRF site. 



1. Vegetation . 



Levy (1976) conducted a complete vegetation study of the FRF site. A 

 vegetation map of 11 different communities in the area is shown in Figure 54. 

 Permanent plots were located in each of the designated communities. The 

 results of the study showed the flora to be composed of about 178 species and 

 132 genera representing 58 families (App. E) . Six of the plant communities 

 correlate with the communities generally common to the Outer Banks: fore- 

 dunes, wetlands, oceanside shrub, sound-side shrub, low dune grass, and bare 

 sand. The remaining five communities are relatively unique to this site: 

 sound-side disturbed, planted American beachgrass {Ammophila breviligulata) , 

 planted bitter panicum (PaniGum amovutum) , sandgrass-buttonweed {Tviptasis 

 purpurea-Diodia teres), and spurge-sandgrass (Euphovbia polygonifolia- 

 Triptasis purpurea) . 



In September 1978, CERC reestablished approximately two-thirds of the 

 previous plots, which could be located, and added more. Plant species were 

 collected and identified, and the vegetation was mapped for comparison with 

 aerial photos at scales of 1:2000 to 1:34000. Optimum scales for identifying 

 vegetative species, associations, communities, and zones were also determined 

 in the comparison. 



a. Dune Vegetation . In April 1972, before CERC obtained the FRF site, 

 the U.S. Navy sprigged the area with American beachgrass. In 1973 and 1974, 

 North Carolina State University conducted experiments on propagation, han- 

 dling, processing, and planting of bitter panicum, American beachgrass, and 

 sea oats {Uniota panioulata) in the northern part of the site about 300 meters 

 inland. By the fall of 1974, bitter panicum was the most successfully estab- 

 lished. Fertilizer applications were necessary to retain the vigor of the 

 planted stands. The results of this study were reported by Seneca, Woodhouse, 

 and Broome (1976). Although the actual plantings are no longer clearly delin- 

 eated, the general area is still identifiable from the air (see Fig. 4). 



b. Marsh Vegetation. Experimental marsh plantings were established 

 between April and September 1973 on the sound-side shore of the site to 



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