THE TAPPING OF RUBBER PLANTS 63 



have been depleted more or less by the previous tapping, 

 may be replenished, as otherwise each successive tapping 

 period will leave the reserve food- supply more and more 

 exhausted with the possibility of injury to the tree or 

 deterioration in the quality of the latex. He further 

 expressed the opinion that an interval of rest during a 

 tapping period would in many cases be beneficial to the 

 trees. Another point which he considered of importance 

 was that it will be inadvisable to tap renewed bark 

 until it has regained its normal condition as evidenced 

 by the presence of starch in the cells. 



This work of Fitting has served to emphasise the 

 necessity of considering the probable physiological effects 

 of the continued use of any system of tapping before 

 advocating its adoption on a large scale, and some of 

 the points which he raised, such as the necessity for 

 periods of rest for the trees, may become of considerable 

 importance when plantation trees have been tapped 

 sufficiently long for the full effects of the tapping 

 system employed to become apparent. Mr. E. Bateson, 

 Assistant Mycologist in the Federated Malay States, 

 has been conductmg further experiments, on the lines 

 suggested by Professor Fitting, on the depletion of the 

 food-reserves of Para trees by tapping and the effect upon 

 the vitality of the trees. It is stated that the research 

 has brought some interesting facts to light which it is 

 expected wiU have a direct bearing on many questions 

 comiected with tapping, but the detailed results have 

 not yet been published.* 



The plan of dividing the stem into four or more vertical 

 sections and tapping these in rotation has been widely 

 adopted on plantations, and is now the most general 

 method of tapping Para trees. This system, it may be 

 mentioned, had been advocated by Ridley, and in a 

 modified form by Wright, before the results of Fitting's 

 experiments were published, in order to ensure that the 

 renewed bark should not be tapped until four years 

 old. 



Tapping Systems. — A brief review of the principal 

 methods employed in tapping rubber trees may now be 



* Reports of Director of Agriculture, Federated Malay States, for 1 91 1 

 and 1912. See also paper by Dr. S. V. Simon in Der Tropenpflanzer, 

 1913, pp. 63, 119, and 181. 



