Figure 57. Natural invasion of plants into area protected from salt spray, wind, 

 inundations, and blowing sand by the artificial dune line (1 ,200-f oot sea 

 oats dune). Upper aerial photo shows dune line in July 1973. Narrow dark 

 line across center of photo is the 75-foot-wide, 11 -foot-high artificial 

 dune, backed by a 300-foot-wide strip of naturally invading species. A 

 zone of barren migrating sand encroaches upon the vegetated plains in 

 background, but the artificial dune has choked off its fresh sand source. 

 Lower ground photo shows same area, viewed northwest from top of dune 

 line, July 1974. 



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