Cross section profiles indicated that American beachgrass dunes 

 moved seaward more rapidly and had more gentle side slopes than 

 bitter paniciim dunes » These findings and other observations suggest 

 that American beachgrass dunes can repair themselves more rapidly 

 following storm attack than dunes with bitter panicum or sea oatSa 



The length of the growing season, and the width and number of 

 leaves per unit area may be factors related to differential sand 

 accumulation by the three dune grasses tested. The leaves of bitter 

 panicum are wider and generally fewer per unit area than those of 

 either American beachgrass or sea oats. Therefore, bitter panicum 

 may not be as effective at trapping sand. The relatively short (May 

 to October) growing season of bitter panicum compared to the 

 relatively long one (February to November) for American beachgrass 

 at this latitude may be one of the reasons for not accumulating as 

 much sand as American beachgrass. The growing season of sea oats 

 coincides closely with that of bitter panicum; other factors, such 

 as leaf width and density, may be responsible for the differential 

 sand trapping between the two species. Since bitter panicum has a 

 longer growing season at a more southerly latitude, it is probably 

 a better dune builder farther south. 



Sand accumulation and dune profile data suggest that bitter 

 panicum should not be used in monospecific plantings to build dunes 

 along the North Carolina coast. The results indicate that the mixed 

 species planting is almost as good at dune building as monospecific 

 stands of American beachgrass. These mixed species plantings are 

 ecologically more desirable because of the insect, disease, and 

 physiological problems associated with American beachgrass at this 

 latitude. In a mixed species planting of American beachgrass, bitter 

 panicum, and sea oats, a dune can be built primarily by the sand 

 trapping potentials of American beachgrass and sea oats; when American 

 beachgrass begins dying out, it can rapidly be replaced by the other 

 two native grasses to stabilize the area. The principal values of 

 bitter panicum are in stabilizing sandy coastal areas and in mixed 

 species plantings to build and stabilize coastal dunes in the 

 southeastern United States. 



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