THE PARA RUBBER TREE 



131 



Diu'ing 1909 further tapping experiments were carried 

 out at Aburi on groups of Para trees 25 in. or more in 

 average gii'th at 3 ft, from the ground, and the results 

 are summarised in the following table : 



These experiments were continued diu-ing 1910 and 

 1911 on four groups of trees, which were tapped every 

 other day for periods of seven to ten months during 1910 

 and throughout the following year. The results obtained 

 are summarised below : 



No. oi trees. 



I. 24 trees 

 1910 



19111 

 II. 15 trees : 

 1910 



1911§ 

 III. 15 trees 

 1910 



1911 

 IV. 25 trees 

 1910 



1911 



Average 

 girth . 



System of 

 tapping. 



26 HaU spiral 



29-6 j Do. 



1 



24 ' Half spiral 



28 I Do. 



n„i V incisions 



^ and paring 



30 ! Do. 



2-1 V incisions 



* and paring 



30 Do. 



No. of 



tappings. 



Total 

 yield 

 of dry 

 rubber. 



lb. 02. 



f86during||29 9 

 1.7 months J , 



131| 



44 3^ 



|129durmg|l3i ^ 

 \.10 months J 



152 j32 11i 



f 130 during \ 02 , 

 UO months/ ^ 



Average 

 yield 

 of dry 

 rubber 



per tree. 



152 



31 12 



(89 during! „„ ,., 

 L7 months/ **" ^"^ 



151 



50 



lb. oz. 

 I 3-7 



1 12-3 



2 1-8 

 2 5-4 

 2 2-2 

 2 2 



1 3-7 



2 



Average 

 yield 

 of dry 

 rubber 

 per tree 

 at eacb 

 tapping. 



0-23 

 0-21 

 0-26 

 0-24 

 0-26 

 0-22 

 0-22 

 0-21 



* These were the 14 trees tapped in 1908 ; see p. 130. 



t 25 trees tapped in 1911. 



J Tapping discontinued November 9, 1911. 



§ 14 trees tapped in 1911. 



10 



