Experience has shown the number of viable seed per liter varies from as 

 low as 500 to as high as 27,000. A rule-of- thumb estimate generally used 

 is 10,000 viable seed per liter (10 per milliliter). When planting, the 

 volume of seed applied per unit area can be adjusted according to the 

 results of the germination studies. The rate used as standard is 100 

 viable seed per square meter. This rate can be adjusted up or down, 

 depending on amount of seed available and the exposure of the site. 

 Fewer seed are necessary in a protected area; heavy seeding rates increase 

 the chances of successfully establishing seedlings in areas exposed to 

 wave action. 



g. Elevation . The elevation range over which seeding is an effec- 

 tive means of establishing new stands of S. altevniflova is less than the 

 elevation range of transplants. Seedlings are not as hardy as transplants 

 and are not as able to tolerate the rigorous conditions of inundation and 

 wave action characteristic of the lower elevations of the intertidal zone. 

 Observations at Beaufort and Snow's Cut illustrate this point in a quan- 

 titative manner. 



At Beaufort, an average elevation of several points along the edge of 

 a natural marsh near the seeding experiment, indicated the lower limit of 

 growth to be 0.43 meter above MLW (mean low water). However, seedlings 

 produced by planting 11 April survived only as low as 1.02 meters above 

 MLW. The elevation of the upper edge of the natural marsh was 1.15 meters 

 above MLW. Therefore, the part of the elevation range normally occupied 

 by S. altevniflova which was effectively colonized by seeding was between 

 1.02 meters and 1.15 meters or a range of 0.13 meter. This amounts to 

 about 19 percent of the 0.72 meter elevation range of the grass at Beaufort. 

 Tide tables list the mean tide range at Beaufort as 0.76 meter. Seedlings 

 produced from seed planted 21 June had an average lower limit of survival 

 of 0.93 meter above MLW. The area colonized represents about 31 percent 

 of the elevation range of S. altevniflova. Apparently the late-planted 

 grass was able to survive at the lower elevation because it was not 

 subjected to storm- induced wave action as was the earlier planting. 



Seedlings were successfully established over a larger part of the 

 elevation range on a dredge island in the Cape Fear River near Snow's Cut, 

 tide range 1.2 meters. Transplants survived from 0.25 to 1.41 meters 

 above MLW or a range of 1.16 meters. Seedlings survived down to 0.79 meter 

 above MLW which is a range of 0.62 meter or about 54 percent of the 

 elevation range at this location. 



h. Protection from Blowing Sand . Covering of seedlings by windblown 

 sand appears to be a primary cause of failure of natural S. altevniflova 

 on sandy dredged material. If there is sandy material above the inter- 

 tidal zone, sand can be blown from these higher elevations until it 

 becomes armored with shell or covered with vegetation. When establishing 

 S. altevniflova on these sites by seeding, it is necessary to protect the 

 area with a sand fence, a vegetation strip such as Ammophila bveviligulata 

 Fern. (American beachgrass) , S. patens (Ait.) Muhl. (saltmeadow cordgrass), 

 Panicum sp., or preferably a combination of fencing and vegetation. 



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