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was not uniform; the north end of the study area gained no sand. Plantings, 

 50 feet (15 meters) wide seaward of existing foredunes proved to be an 

 effective dune-widening technique. This has provided a 125-foot (38 meters) 

 dune base versus an 80-foot (24 meters) dune base from initial 100-foot-wide 

 (30 meters) plantings. 



Sand-trapping rates averaged 6.3 cubic yards (4.8 cubic meters) per linear 

 foot per year on foredunes of experimental plantings versus 4.0 cubic yards 

 (3.1 cubic meters) for the unplanted, natural area. However, accumulation 

 rates for the last year were 4.1 cubic yards for planted foredunes versus 

 4.0 cubic yards for the natural foredune. Apparently, the natural area is 

 sufficiently vegetated to accumulate sand as rapidly as planted areas, but it 

 has taken 15 years to reach this trapping efficiency and without a recognizable 

 dune line. Rate of lateral grass spread from initial plantings varied from 

 5.25 to 7.24 feet (1.6 to 2.2 meters) per year. Vegetation studies show little 

 invasion of unplanted species into the planted foredunes. Landward of planted 

 dunes, grass establishment is well ahead of the unplanted area. The unplanted 

 area is more arid. Mean elevations for dune crests 89 months after planting 

 were 19.2 feet (5.9 meters) mean sea level versus 8.6 feet (2.6 meters) for 

 the unplanted area. 



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