Table 25. Second-Year Development of S. alterniftova Plantings* 

 Cedar Island, 13 September 1973 



Sample 



Aerial 



Height 



Number 



Number 



Basal Area 



Number 



Dry Weight 





Flowers/m 2 



Stems/m 2 







(kg/ha) 



(cm) 







(cm 2 /m 2 ) 



1 



14,680 



128 



164 



428 



81 



2 



17,680 



138 



136 



425 



153 



3 



16,200 



140 



112 



336 



127 



4 



6,640 



118 



84 



148 



46 



5 



11,920 



124 



80 



372 



127 



Mean 



13,440 



130 



116 



340 



107 



*0.25 m samples 



Another planting of 1,900 transplants was made on five small areas 

 north of the Radar Tower on 11 and 17 May 1973. This shoreline is more 

 exposed to the northeast and is eroding more rapidly than the area used 

 for planting in 1972. Plants were closely spaced, about 0.3 by 0.3 meters. 

 The total frontage covered was about 90 meters long. Erosion has con- 

 tinued on this area with little net recession of the shoreline, but sub- 

 stantial movement of material back and forth so that only about 20 percent 

 of the plants could be identified as surviving in September 1973 (Fig. 53) . 

 Fewer were in evidence in January 1974, but some of these had grown quite 

 well, some were buried beneath sand and rubble, and the amount of new 

 growth that would appear in the spring was not predictable. Obviously 

 this planting will not be as successful as the 1972 planting nearby, but 

 it could be better than at present. 



Experience in shoreline stabilization suggests that such plantings do 

 have potential for reducing sound-side shoreline erosion in this region. 

 Many eroding sound shorelines are similar to those in the study area at 

 Cedar Island. Any marsh vegetation remaining on them has lost contact 

 with the sound bottom, separated from it by a scarp. The plants can no 

 longer spread back into the bare zone by rhizomes. Further, since turbu- 

 lence along the shoreline is excessive for seedling establishment, there 

 is little possibility for natural revegetation. It is known from work 

 elsewhere that S. alterniflova can be established by transplanting under 

 conditions that are much too rigorous for natural invasion. If vegetation 

 is to be reestablished on these shores, transplanting is the only possi- 

 bility. 



VI. 



THE RELATIONSHIP OF MINERAL NUTRIENTS TO PRODUCTIVITY 



OF SPABTINA ALTERNIFLORA 



The mineral nutrition of S. alterniflora was studied to obtain know- 

 ledge of the relationship of fertility of the substrate material to 



102 



