that for seawater because of evaporation, and leaf death was due to 

 cell plasmolysis. However, Boyce (1954) demonstrated that chloride ion 

 toxicity caused leaf death. He discovered other ions were seldom 

 present in high enough concentrations to produce necrosis. Since 

 necrosis always occurred first at the tip regardless of where the 

 chlorides entered the leaf, Boyce concluded that damage occurred 

 after salt trans location o Salt entrance was increased through wind- 

 induced leaf lacerations, which explained why plants with sessile 

 leaves or leaves densely covered by hair are damaged less by wind 

 action than plants with long petioles and smooth surfaces. He also 

 discovered that increased soil nitrates resulted in decreased cuticular 

 thickness and number of epidermal hairs allowing more frequent 

 lacerations, increased chloride uptake, and reduced salt spray 

 tolerance. 



Wagner (1964) found that salt spray decreased the growth rate of 

 U. paniculata but did not kill the plant. This he attributed to the 

 thick cuticle and other xeromorphic characters of its leaves which 

 reduce surface chloride ion uptake. 



Numerous investigators have classified strand plants according to 

 salt spray tolerance (Wagner, 1964; Costing and Billings, 1942; Wells, 

 1939; and Wells and Shunk, 1938). Costing (1945) studied the salt 

 spray tolerance of 14 species. He found S. patens and Atriplex cocenaria 

 (seabeach orack) unaffected by salt spray, U. paniculata the next most 

 tolerant, and S. sempervirens and C. pimatatus slightly less tolerant. 

 Iva irribvioata, I. frutesoens (marsh elder) , and Borrichia fvutesoens 

 (sea-ox-eye) were moderately tolerant. E. polygonifolia, Chenopodiim 

 anbrosioides (Mexican tea) , and Cynodon daatylon (Bermuda grass) had 

 some tolerance, while Strophostyles helvolva (wild bean) and H. svbaxit- 

 laris were less tolerant, Leptilon canadensis {E. candensis) showed 

 virtually no tolerance to salt spray. 



Other species rated as highly or moderately salt tolerant include 

 A. littoralis (Costing and Billings, 1942), Baccharis halinrifolia 

 (groundsel-tree), I. vomitoria, and M. cerifera (Wells and Shunk, 1938). 



Seneca (1969) found that maximum germination tolerance to salt 

 (NaCl) for A. breviligutata and U. paniculata was between 1 and 1,5 

 percent. Panicum amarulum had an upper tolerance limit between 1.5 and 

 2 percent, while S. patens was about 4 percent. The latter had an 

 average of 53.3-percent germination in 3-percent NaCl. Decrease in 

 germination was attributed not to salt toxicity but to the osmotic 

 differential. Based upon their germination experiments the order of 

 tolerance (from most to least) was S. patens, P, amarulum, U, 

 paniculata, and A. bveviligulata. 



All the above species showed stress in the seedling state but at 

 different levels (Seneca, 1972). Symptoms included an initial twisting 



