Hums, Resins, 



4 



[Jan. 1907. 



Original and Permanent Distance. 



It is taken for granted that the reader is familiar with the sizes of Para 

 rubber plants from their first to their thirtieth year, in different soils and climates ; 

 the question to discuss is whether the original should be the permanent distance. 

 No one who has seen the uncultivated thirty-year-old trees at Henaratgoda can 

 doubt that such specimens require, at the very least, a distance of thirty to 

 forty feet, if they are to be allowed to continue in their growth and maintain 

 a healthy constitution ; what the required distance will be when they are 40 

 to 50 years old it would be unwise to predict. In striking contrast to this are the 

 thin, tall stems of two to four year old trees, and the poor lateral spread of the 

 foliage when they have just reached the tappable size. Between the first year 

 of tapping and that represented by the old Henaratgoda trees, is a gap of 25 years 

 — probably the equivalent of a longer period when the newly-bearing trees are regu- 

 larly tapped, year in and year out. Iam of the opinion — though I may be wrong — 

 that it is absolute folly to plant, in a clearing, Para rubber trees alone, at a distance 

 which they will require when thirty years old ; we are dealing with a species which 

 does not, like cacao and similar plants, attain the greater part of its maximum size in 

 the first six or seven years, but with one which continues to grow, year by year, 

 and even when thirty years old, still keeps on growing and throwing its roots 

 into new soil. Though Para rubber trees continue to grow in this manner, though 

 the ultimate size to which they will attain can only be roughly guessed at from our 

 scanty knowledge and experience, yet we know that when their stems are only 20 

 inches in circumference they yield marketable rubber in very satisfactory quantities. 

 Pour to six years is a long time to wait for the first returns, and from a commercial - 

 standpoint the distance at which trees can be planted, without entailing undue 

 interference in general development, and brought into bearing in their fourth 

 year onwards, is the one to be decided. Of course, when the trees are Avidely planted 

 they come into bearing as early as when closely planted, but there is no very 

 great difference in the dimensions of trees planted at widely different distances, 

 up to their fourth year ; the growth in the first four years is not as conspicuous 

 as in later years, and even in the richest soils there is a limit, notwithstanding 

 statements to the contrary, to the root and foliar development of Para rubber 

 plants just as there is to parts of other cultivated plants. 



The closer the trees are planted, within reasonable limits, the greater is the 

 yield, per acre, in the first tapping year, a consideration 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 remembered that one tree which will give 1 lb. of rubber per 

 year, now, is about equal to the value of one double its size which yielded 2 lb. 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 cacao, coffee, camphor, tea, Erythrinas 

 and Albizzias, etc. 



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 



