Figure 10. Erosion period for Cedar Island, North Carolina 

 (8 years after planting) . 



salt marsh plants on bare substrates provided valuable experience which was 

 applied later to the subject of shore erosion control with vegetation 

 (Woodhouse, Seneca, and Broome, 1976). 



Researchers in other coastal regions have found that shoreline stabiliza- 

 tion with plants can be successful — Garbisch, Woller, and McCallum (1975) in 

 Chesapeake Bay; Webb and Dodd (1978) in Galveston Bay, Texas; Newcombe, et al. 

 (1979) in San Francisco Bay, California. Based on these studies, design 

 criteria for vegetation stabilization projects were developed (Knutson 1976, 

 1977a.). The U.S. Army Engineer Waterways Experiment Station (1978) conducted 

 a nationwide study program on salt marsh establishment on dredged material in 

 the mid-1970's resulting in design criteria for this use of vegetation. 



Hall and ludwig (1975) evaluated the potential use of marsh plants for 

 erosion control in the Great Lakes. They concluded that there were few areas 

 suitable for this method of shore protection because there are few sheltered 

 shorelines. Marsh plantings are also subject to winter icing conditions and 

 fluctuating lake levels in this region. However, vegetation can be used to 

 stabilize upland areas. The roots of terrestrial plants add stability to the 

 soil, retard seepage, and reduce surface runoff (Great Lakes Basin Commission, 

 1978; Gray, 1974, 1975; Dai, Hill, and Smith, 1977). Information on surface 

 erosion and various techniques for its control (dewatering, slope grading, and 

 planting ground cover species) are available from the Soil Conservation 

 Service or County Agriculture Extension Agents. 



In Alaska, a relatively short growing season, broad tidal ranges, high 

 energy conditions, and icing prevent the use of salt marsh vegetation for 

 erosion control. This alternative has not been used in the limited bays and 

 estuaries of Hawaii. 



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