PARA-RUBBER CULTIVATION 415 



Recently a Ceylon planter 1 has introduced a pricking 

 system as a complete substitute for the paring method. It has 

 not as yet met with much favour. 



Pricking has been blamed for the production of burrs and 

 nodules in the renewed bark. Petch 2 has stated reasons for 

 this view. If correct, it is a serious drawback to the use of the 

 pricker. Though opinion generally seems rather opposed to 

 than in favour of pricking, either in conjunction with paring 

 or alone, yet it is still a debatable point. The paring method 

 on the half herring-bone system is giving excellent results on 

 estates and is very systematic. 



The question may be asked : Will the tree stand this some- 

 what severe treatment of removing gradually its bark up to a 

 height of six feet ? So far, no pronounced ill-effects have shown 

 themselves. The bark on the excised area is renewed satis- 

 factorily and this secondary covering is as rich or even richer 

 in latex than the primary bark. This is on a par with the 

 cinchona tree, which gives a greater yield of quinine from its 

 renewed bark. 



It has not yet been settled as to the time which should elapse 

 before the reformed bark should be tapped. Four years has been 

 considered a suitable period, but this may be possibly longer 

 than is really required. Some results seem to show that if the 

 new bark is tapped early, the rubber is of an inferior quality, 

 even though the latex may be abundant. 



Wickham, 3 in his criticism of plantation methods, views with 

 disfavour this system of removing the bark, and thinks that, in 

 the long run, the incision mode of tapping, as employed on the 

 wild trees in the Amazon, will be found to be preferable. His 

 views seem generally to run counter to the practices in the 

 East. At the same time, the opinions of one who is so well 

 acquainted with the Brazilian rubber industry are not to be 

 lightly laid aside. 



High Tapping. — It has already been mentioned that, as a rule, 

 it is not advisable to continue the tapping of a Hevea trunk 

 above six feet. In the first place, the yield of latex is much less 

 from the upper parts of the stem, and secondly, high tapping 



1 Northway's Tapping System — see article in India-Rubber Journal, 1909, 

 vol. xxxviii. p. 225. 



* Petch, Circular, Roy. Bot. Gardens, Ceylon, 1909, vol. iv. No. 18. 

 3 Wickham, loc. cit. p. 38. 



