the United States Department of Agriculture, 

 as follows : ' 'The planted trees at La Zacualpa 

 abundantly demonstrate the practicability of 

 rubber culture." 



The successful production of rubber and 

 growth of these trees, combined with their 

 present healthy state, has proved the fact that 

 Castilloa Elastica can be easily cultivated in its 

 native habitat, with large profits. 



Cultivated trees are raised from the seed, 

 and begin to yield milk during the sixth year 

 from date of planting. 



The trees have no natural enemies, as, by 

 reason of the quantity of resin and albuminoids 

 contained in the milk, they are not molested 

 by worms, insects, birds or animals. During 

 the first few months of the tree's life, when 

 the stock is in a watery state, it is subject to 

 attack by gophers, against whom warfare is 

 waged; as growth continues the flavor changes 

 and becomes distasteful, thus rendering the 

 tree immune. 



Owing to the successful conditions noted 

 above, this plantation has been extensively de- 

 veloped, and under the care of expert rubber 

 cultivators about 3,000,000 rubber trees are 

 growing vigorously. 



The cultivation of rubber is a new enterprise, 

 calling for the most careful study, and is a 

 notable addition to the world' s varied industries. 



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