l S 
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 ak 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 o f 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 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 w 
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 wp want a hatdy 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 
