428 The Philippine Journal of Science 1921 
of the year, supplied with salty water. During November, at 
which time the crop is the heaviest, the river is reported to be 
free from salt. At this season the fruit is poorer in quality 
and is more or less seedy. 
The chemical analyses of water and water extraction of or- 
chard soil from the Nakorn Chaisri region showed that in June 
the salt content is great ; and the analysis from the Bang Bakok 
region showed only a trace of salt to be present. This would 
indicate that there is a difference in the salt content of the water 
throughout the year in both localities. The difference in quali- 
ty of the Kao Pan grown in these regions may then be due to 
the variance in the salt content of the soil and the water used 
for irrigation. According to the people at Tachin, 5 or 6 kilo- 
meters from the gulf, the fruit cannot be produced there because 
of the extreme salt content of the river water. 
The salty character of the water used for irrigation appears 
to account for the superior flavor of the Nakorn Chaisri pum- 
melo. The commercial pummelo, Kao Phuang, grown in the Dao 
Kanong region of the Menam Chao Phaya just below Bangkok, 
seems to react to the salt influence when grown in Nakorn 
Chaisri, where it produces a better quality of fruit. The flavor 
is reported to be improved also when the Kao Phuang is grown 
down Menam Chao Phaya River near the Gulf of Siam where the 
water is saltier. In these regions, the system of irrigation with 
salt water is similar to that practiced in the Nakorn Chaisri 
region, and the water of the Menam Chao Phaya would un- 
doubtedly be somewhat of the same salty character as that of 
the Tachin. 
Experiments have been conducted in various parts of Siam to 
test the relation of salt to fruit production. The salting of 
pummelo trees to produce better quality is by no means a new 
practice, nor is it restricted to Siam. Cameron 13 cites a case 
of salting in India. Under Citrus decumana Linn, and the Can- 
ton pummelo he writes the following: 
A dressing of salt to the roots of the trees I have been told by a friend, 
who tried it upon several in his garden, has a surprising effect in improv- 
ing the quality of the fruit, renderng it tender as an orange, and all but 
bursting with juice. 
An instance of salting a Nakorn Chaisri seedless pummelo 
tree at Bangkok was given us by Dr. Yia S. Sanitwongse. The 
18 Cameron, J., Firmingers Manual of gardening for India. Thackei 
Spink and Co., Calcutta (1904) 280-281. 
