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tions made by Kearney *° show that the salt content of some sea beaches 
is indeed so low that he is justified in making the statement that so far 
as this factor is concerned, plants growing thereon are not halophytes. 
Walker °° in studying this question in regard to the Philippine Islands 
finds only a trace of salt in the soil of the sea beach, and tests made of 
several specimens of sand from the Lamao strand confirm these results.** 
A surface soil, collected just at the upper limits of high tide, where 
runners of [pomoea are present, shows 0.25 per cent of sodium chloride; 
one 6 meters back of this, where seedlings of Hrythrina indica are 
abundant, gives only 0.004 per cent of salt; one 9 meters above high 
tide had a content of 0.005 per cent, and a sample just beneath the 
surface, 26 meters inland, gave 0.003 per cent. Ordinary, cultivated 
soil is known to contain from 0.02 to 0.2 per cent of sodium chloride. 
It is therefore out of the question to assume that the salinity of the 
strand has brought about the ecological adaptations for many beach 
plants. 
On the other hand, salt spray is known to be deposited in considerable 
quantities on the leaves of trees growing near the beach. At any time 
of the year this can be detected by taste, and it is especially noticeable 
after a typhoon. It is a common observation that considerable quantities 
of this spray will injure and eventually kill delicate leaves of plants not 
accustomed to such habitats. During a prolonged typhoon in Manila, 
comparative observations were made on Terminalia catappa, the natural 
habitat of which is on the seacoast, and Artocarpus incisa, which has 
much more delicate leaves and the natural habitat of which is in more 
protected situations. The effect of the salt spray on Terminalia was 
hardly noticeable, while the whole of the seaward, and much of the 
landward, side of Artocarpus lost its leaves by a gradual withering, due 
to the effect of the salt spray. Therefore, leaves of trees growing on the 
frontal zone of the beaches must have characteristics which will enable 
them to withstand the physiological drying effect of sodium chloride. 
Coast lines are essentially windy places. Since no protection is offered 
to the vegetation, the frontal zone is constantly being exposed to the 
drying action of strong winds; in this respect it is comparable to the 
habitat of the ridge vegetation on the mountain and the likeness finds 
ecological expression in the stunted growth and the often “umbrella- 
hike” shape of the trees. 
The incapacity of the sandy soil to hold water is well known and tests 
of samples of sand from the Lamao beach, taken near the limits of high 
* Kearney, T. H.: Are plants of sea beaches and dunes true halophytes? Bot. 
Gaz. (1904), 37: 424-436. See this for literature of the subject. 
“The coconut and its relation to production of coconut oil. Walker, FH. 8.: 
Phil, Journ. Science (1906), 1: 59. 
* Analyses made by L. A. Salinger of this Bureau. The percentages given are 
by weight of salt as compared with the air-dry weight of soil. 
