ECONOMIC POSSIBILITIES OF MANGROVE SWAMPS. 55 



The yield of bark pei' tree -was determined by felling three representative 

 trees each of bacauan and pototan and stripping and weigliiug the bark. 

 Bacauan averaged 140 kilograms per tree, pototan 19U kilograms. On 

 this basis the area will yield 20.6 metric tons of bacauan bark per hec- 

 tare, and 5.8 tons of pototan. We may safely state the yield at 20 tons 

 per hectare of bark worth about 40 to 45 ^^ pesos per ton, at 0.28G peso 

 per kilogram unit of tannin, allowing 50 per cent for moisture. 



The restrictions placed by the Bureau of Forestry upon the exploita- 

 tion of the swamjis Avill depend largely upon their condition at the 

 outset. However, it is understood that in virgin swamps the cutting of 

 trees over 20 centimeters in diameter will be permitted provided the 

 wood is put to some commercial use. It is said that in Borneo and 

 Queensland the standing trees are stripped as high as convenient and 

 the tree left to die and go to waste. I am convinced that the bark can 

 be gathered more economically by felling the tree and obtaining all the 

 bark. A tax of 3 pesos per metric ton is levied on the dry bark. 



It is not my purpose to take up the question of the disposal of the 

 wood. This problem certainly is the most serious one confronting the 

 prospective exploiter of swamps distant from Manila. The market for 

 mangrove woods for structural purposes at present is extremely limited. 

 The firewood industry has been suggested as an outlet. Taxes were paid 

 on about 200,000 cubic meters of firewood in 1909. However, most of 

 this supply comes from swamps near the markets for which it is in- 

 tended. It sells on an average all over the islands for about 25 pesos 

 per 1,000 rajas (about 5 to 6 cubic meters). After paying for logging, 

 sawing, splitting, and meeting transportation charges of at least 1.50 to 

 2 pesos per cubic meter and a tax of 1 peso there would be an ex- 

 ceedingly small profit even if present prices could be maintained. 



If a market can not be found for the wood, destructive distillation 

 might be resorted to, as there is e\eTy reason to believe that these woods 

 are especially suitable for that purpose. The lack of a near market for 

 large quantities of charcoal would of course be a great drawback. Aside 

 from this, there can be no question but that such swamps can be ex- 

 ploited at a good profit. 



Shipment of the raw bark might not prove profitable. Mangrove 

 barks are quoted ^- at 18 dollars per ton in the United States. This 

 is an extremely low" price per unit of tannin, even in crude materials. 

 It is probably due to the high coloring power of air-dried barks. It is 

 possible that by kiln drying a better price might be obtained. However, 

 Australia offers a much better market for such materials. The demand 

 is steady and the better classes of tan barks bring as much as 7 pounds 



" This is not the market value of the bark as such. See footnote "a" to 

 Table I. 



"Hide and Leather, Oct., 1910. 



