228 THE ASSAM RUBBER TREE 



Burma on the hillsides up to 5,000 ft., thrivmg best in 

 Assam up to 2,500 ft. and in Burma between 2,500 and 

 3,500 ft. 



Ficus elastica is a very large evergreen tree which 

 may attain a height of 120 ft. The branches give rise 

 to numerous aerial roots which grow down to the soil and 

 then thicken, forming subsidiary stems. The leaves are 

 very characteristic, being dark green, large, and glossy. 

 It is stated that at Charduar m Assam two varieties may 

 be distinguished, one of which has much larger leaves 

 than the other. The " fruits " are small, about the size 

 of a pea, and contain from sixty to eighty minute seeds. 

 In a wild state the trees usually develop as epiphytes on 

 other trees, which are usually killed later by the enveloping 

 roots. 



The greater part of the rubber obtained from Ficus 

 elastica is collected from wUd plants, but the trees have 

 been cultivated in India, at Kulsi and Charduar in Assam 

 and on a smaller scale in Madras and Mj^sore, and also in the 

 Malay Peninsula, Java, and Sumatra. The tree is known 

 as " Rambong " in the Malay Peninsula, and " Karet " 

 in Java. 



Some years ago a considerable number of Rambong 

 trees were planted in the Federated Malay States, but 

 it has been found that the tree is much less satisfactory 

 as a source of rubber than the Para tree, and it has con- 

 sequently fallen into disfavour and is now no longer 

 planted. On some estates the Rambong trees have been 

 cut out and replaced by Para trees. The principal 

 reasons for this adverse opinion are that the annual 

 yield of rubber per acre from Ficus elastica trees is much 

 less than from Para trees and that it diminishes rapidly 

 when the trees are regularly tapped. In consequence 

 of the latter fact the trees have to be rested periodically 

 before they again yield well. In addition, the habit of 

 growth of the trees renders them much more difficult to 

 tap than Para trees and the latex is not so readily coagu- 

 lated. For these reasons Ficus elastica camiot be recom- 

 mended for cultivation in any district where the con- 

 ditions are suitable for growing the Para tree, and even 

 in Assam it seems doubtful from the results obtained 

 on the Government plantations, whether the cultivation 

 of Ficus elastica would prove remunerative unless under- 



