13 



we had better give up rubber planting. At least as far as Castilla 

 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 bruising 

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

 than leaving them undisturbed. In any case, the price of stump- 

 ing 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 tap- 

 ping 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 danger from 

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

 are recommended. How about the jungle belts that should be lett 

 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 it costs 

 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. 



Selection of Seeds. 



We have noticed a decided increase in the rapidity of growth 

 for every year since selection of seeds has been practised on 

 La Zacualpa. This naturally stands to reason. Still the necessity for 

 careful selection of seed for a rubber plantation does not seem to have 

 been accorded the attention it requires. A farmer now-a-days is 

 very particular about his seed corn, and a fruit grower thinks twice 

 before he decides about the kind of tree he plants. Suppose a corn 

 farmer sows seed that is very uneven in size, some fresh in the 

 milky or green stage, others old and eaten by weevils. What kind 

 of a crop will he get ? When we want a hardy stock of fruit trees 

 we take care to select only the best seeds. But a rubber planter 

 seems to think that any seed is good, any tree is suitable as long as 

 it is a Castilla. It must, however, be borne in mind that the whole 

 life of the tree, its healthiness, size, strength, its amount of rubber, 

 all depends upon the start it has. Unlike so many other agricultural 

 industries, rubber culture cannot be immediately benefited by a 

 lesson learned through bitter experience, because a tree, once 



