78 PARA RUBBER. 



that the rate of growth of the Para rubber tree in Ceylon is such that 

 a circumference of 20 inches cannot be attained much before the 

 fourth, fifth, or sixth year, it is obvious that, under ordinary 

 methods of cultivation, all ideas of extracting rubber from trees 

 under these ages should not be encouraged. 



One manufacturer is reported* as saying that the rubber does not 

 attain its full strength until the tree is at least 8 or 9 years old, and 

 material from younger trees "has not the the strength of hard cure 

 Madeira line Para, and is uneven in strength." It is also asserted 

 that there is no difference noticeable in the rubber from 8-year-old 

 trees from different plantations, but it is not yet safe to use it for the 

 finest work, such as thread and the best bladders. 



Minimum Size for Tapping. 



If the tree has a circumference of much less than 20 inches, tapping 

 cannot be recommended, because the available tapping area 

 is too small. The production of new tissue would be a strain 

 on the young plant, and the thin bark tissues would probably 

 be quickly cut away long before the desired quantity of rubber had 

 been obtained. 



The illustration on Plate 7 , Series D , clearly indicates this. If the 

 circumference is anything above 20 to 24 inches, a yard from the 

 ground, and the tree is four to six or more years old, it can, in 

 Ceylon, be lightty tapped. I have seen good rubber from such trees. 

 A tree 24 inches in circumference cannot have more than two 

 spiral curves for tapping. 



On one estate in Ceylon 41 trees of considerable height, but having 

 a circumference of from 18 to 25 inches a yard from the ground, 

 gave with very light tapping during March and April 19| lb. 

 of dry rubber, which was favourably reported upon in Europe. 



From the foregoing remarks it is clear that the question of the 

 available tapping area at a given age must be considered ; it is as 

 important as the age of the trees. A minimum circumference of 20 

 inches, a yard from the ground, and a minimum age of 4 to 6 years 

 can be accepted for most rubber properties, the better developed 

 trees being tapped first. 



HOW TO INCREASE THE TAPPING AREA. 



The foregoing statements refer to trees of known ages that have 

 attained the minimum circumference when allowed to develop very 

 long and slender stems. But it has been previously remarked 

 that by pruning the trees at a certain stage the plant may be made 

 to increase in girth at the expense of the longitudinal growth, and a 

 very striking illustration is to be seen in the first clump of old Para 

 rubber trees in the Henaratgoda Garden. The dimensions of 

 forked and straight-stemmed trees on various estates in Ceylon 

 have been previously given. 



* India Rubber World, December, l'JOo. 



