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greater is the yield per acre, in the first tapping year, a consider- 

 ation not to be lost sight of in view of the wavering in the price 

 paid for the raw rubber during the last ten years ; in fact it is 

 the condition of the present market as compared to that of past 

 years, wherein lies the main wish to possess a large number of 

 trees of a tappable size as early as possible. It should be re- 

 membered that one tree which will give lib. of rubber per year, 

 now, is about equal to the value of one double its size which yielded 

 2lb. of rubber in 1894 ; no one can dispute the desirability of 

 placing produce on the market while the price is high. 



If the principle here outlined, of allowing a definite area of soil 

 according to the size and age of the tree is granted as being 

 reasonable, our next point is to discuss how the distance can, with 

 advantage, be gradually increased. It is obvious that an increased 

 root area can only be given by the destruction or removal of trees 

 already existing, a conclusion which brings forward the methods 

 of procedure possible or advisable, when a Para rubber property 

 is interplanted with trees of its own kind or with those of cocoa, 

 coffee, camphor, tea, Erythrinas and Albizzias, &c. 



CLOSE PLANTING AND THINNING OUT. 



The possibility and method of thinning out rubber trees on a 

 closely-planted estate was discussed in my original paper. The 

 great outstanding advantage of this system is that a return is 

 obtained by tapping only intermediate trees, and can be carried 

 out with the definite idea of extracting every possible particle of 

 rubber from such trees, and finally felling them and uprooting the 

 stumps. But, as I have previously pointed out, it can only be 

 recommended on the understanding that the estates will be thinned 

 out after the fourth or fifth year and all root stumps extracted. 

 The practicability of extracting rubber, valued at over 5s. per lb., 

 from trees having a circumference of 18 to 20 inches — that is in 

 their 4th or 5th year — has been proved long ago, and is takisg 

 place to-day on some very prominent and valuable estates ; it is 

 difficult to understand the reason for any statement to the contrary, 

 in spite of what has and is still being done. 



An alternative method of obtaining rubber from such trees- 

 by felling them and macerating the bark — has been suggested. 

 At the present time this cannot be recommended, first because the 

 yields thus obtained have been less than when the trees have been 

 tapped standing ; and, secondly, because the rubber obtained by 

 maceration appears to suffer in quality owing to its being mixed 

 with the sap of the cortical cells ; nevertheless, we know that 

 rubber is thus obtained from other plants, and the results obtained 

 justify further investigation. 



The objections which have been raised against thinning-out are 

 briefly that (1) planters are not keen to thin out, fell and uproot 

 the plants, (2) it is a very difficult matter to kill a Para rubber tree 

 by tapping, (3) there may be interference in the growth of the 

 remaining plants, (4) diseases may be encouraged to flourish on 

 the weak trees which are not removed. 



It is admitted that by some systems of tapping it is very difficult 



