PARA RUBBER. 



83 



In Ceylon tapping every day throughout alternate months, or 

 every day when moisture is abundant, or on alternate days through- 

 out the year, has given good yields. 



The following results of experiments at Henaratgoda are of value as 

 they show what yields have been obtained by tapping trees of 

 similar age at varying intervals. The tapping operations were 

 commenced in September, 1905, and ended in February, 1906, the 

 full spiral system being adopted in all the cases quoted below, 

 from the base to a height of five to six feet. 



These results suggest that the average amount of rubber, obtainable 

 per tapping operation, is likely to increase when an interval of 

 one or more days is allowed between successive tappings. They 

 also indicate that the average yield, per tapping, is better when the 

 trees are tapped every alternate day than when tapped once per 

 day or once per week. From a practical standpoint, however, the 

 total quantity of rubber obtainable when the trees are judiciously 

 tapped at regular intervals is of more importance than the deductions 

 just made ; the latter must not be construed as contradicting the 

 accepted theory of wound response previously discussed. 



Yield of Dry Yield of Rub- 

 Frequency of Number of Number of Rubber per ber per tap 

 Tapping. Times tapped. Trees. five trees. ping, per 



fivei 



Every day (D) . . 168 



Every alternate day(E) 83 



Twice per week (A) .. 57 



Once per week (F) 28 



Once per month (G) . . 7 



5 



5 



28 



5 



5 



