planted blocks between November 1973 and November 1974. There was 

 evidence of some accumulation along the unplanted profiles mostly in 

 the middle and upper zones where Spartina alterniflora is naturally 

 invading. 



Except for transect 7, sediment accumulation by the planted marsh 

 during the 12-month period, November 1973 to November 1974, slowed sub- 

 stantially for no obvious reason. The explanation probably lies in 

 changes in availability and movement of sediments during this period. 

 However, the plantings appear to have stabilized these areas; there 

 was gain on one planted transect and no loss on the others. 



2. Plant Spacing . 



Spacing of Spartina alterniflora transplants is not critical on 

 protected sites. With a reasonable survival rate, areas transplanted 

 3 by 3 feet in the spring will have complete cover by the next spring. 

 A wider spacing seems questionable since it places more stress on 

 survival rate and does not result in substantial savings. 



Under a more rigorous eroding shoreline condition, where the main 

 objective is early stabilization, a close spacing may be justified. A 

 situation was encountered at Pine Knoll Shores where closer spacing 

 appeared to make worthwhile differences. Data taken in the fall 

 showed growth proportional to planting density and nondestructive 

 sampling in the spring indicated little change over winter (Table 9). 

 However, these data do not fully reflect the condition of the surviv- 

 ing plants. This is better seen in Figures 19 and 20. The plants on 

 the 3- by 3-foot spacing were more severely stressed during the winter. 

 Apparently, the closer spacings dampened wave action and reduced sedi- 

 ment movement sufficiently to significantly affect the vigor of the 

 plants. The plants protected one another, and the required critical 

 mass developed between the 2- and 3-foot spacing. Differences bet- 

 ween the 2-foot and 1.5-foot spacing were not evident at the end of 

 winter. 



The closer spacing did, in this case, improve stand survival and 

 condition and result in more rapid stabilization. The wider spacing 

 may still colonize and cover over later in the year. 



3. Pine Knoll Shores Golf Course . 



Two actively eroding sections in a natural marsh along the sound 

 shore beside the Pine Knoll Shores Golf Course were used in an experi- 

 mental planting (Table 10) . These gaps originated from excessive 

 filling during and following construction of the golf course. Both 

 gaps were crescent-shaped bays bounded by Spartina alterniflora marsh. 

 The gaps probably represented intertidal shoreline indentations that 

 were filled to straighten the shoreline and provide space for the 

 course. 



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