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when we clear the virgin land for rubber planting ? There are 

 hard woods which do not decay for a long time, and during the 

 first few years there is a constant decomposition going on, in the 

 ground and above it, of roots, stumps, branches, and even trunks. 

 Examination will disclose the fact that all of these are affected 

 by some fungus or another, and overground parts also by insects. 

 Do these present any danger to the planted trees ? They certainly 

 do, but as long as the planted trees are sound, they are not likely 

 to be attacked, and there is hardly any other way of preventing 

 disease than by keeping the trees in good condition. One of the 

 main factors affecting the health of rubber trees is the drainage of 

 the soil. Keep the ground well drained, and the trees will be sound. 



It has been suggested that the ground should be stumped 

 before planting, and others have advised digging up the roots 

 after the rubber trees have been cut down. This is all very good, 

 but if we have to stump the ground in preparing our land, I think 

 we had better give up rubber planting, at least as far as Costilla 

 is concerned, To stump or dig up roots in an established stand 

 of rubber is also a method not to be recommended, except in rare 

 instances when absolute necessity arises, such as trenching for 

 isolation of a tree affected by root fungus. The roots of the trees 

 interlace, and any injury to these roots from wounding or bruis- 

 ing them is much more likely to permit an attack by fungus 

 mycelia than leaving them undisturbed. In any case, the cost 

 of stumping would be prohibitive in Mexico and Central 

 America, 



It has been assumed that the tapping " to death" of alternate 

 trees would be dangerous to the health of the stand. Why is 

 tapping of alternate trees more dangerous than tapping every tree ? 

 As soon as all the rubber is extracted, that is in about a week's 

 time, the trees are felled. In that time there has been no 

 opportunity for any ravages of pests. There is a clanger from 

 intermediate or catch crops, such as cocoa or coffee, and still they 

 are recommended. How about the jungle belts that should be 

 left at intervals in a rubber plantation ? Do not these constitute 

 a danger? Might they not become a breeding ground for pests ? 

 Of course, but we cannot eliminate all sources of danger, without 

 making planting impossible. 



There are essentially two ways in which we can start a rubber 

 plantation. One is to treat it as an orchard. In this case we 

 are restricted to a small area and we can naturally take better 

 care of our plants, and probably obtain better results from our 

 individual trees, but it costs more. The other method is planting 

 rubber over large areas as we plant forests of other trees. Such 

 plantations cannot receive the detailed care we can give an orchard 

 but they cost less in proportion to maintain. It is here we have to 

 apply the methods of modern silviculture, and we must apply 

 them in a scientific and at the same time practical and economic 

 manner. As for the ultimate financial results they will be almost 

 identical in either case, although as an investment the smaller 

 place naturally presents a lesser element of risk. 



