15 

 Methods of Selection. 



The process of selection should commence, as 1 have pointed out 

 above, with the seeds. Whatever method of planting is adopted the 

 most important time for selection is when the seedling has appeared 

 and grown to a size which permits the distinguishing of its main 

 features. In order to be able to exercise necessary judgment in this- 

 selection the planter should be thoroughly acquainted with the 

 development of the plant in its various stages. 



1 have previously stated that a great variation exists between 

 individual plants. This variability is evidenced in a large proportion 

 of the trees producin*^ a small quantity only and often an inferior 

 quality of latex. Such a lack of uniformity necessitates a subsequent 

 sorting and grading of the latex if a good result is to be obtained. 

 If latex from all kinds of trees is indiscriminately mixed together 

 the result will be a lowering of the standard. From a planter's 

 view-point uniformity of stand is desired, and to attain such a result 

 systematic seedling selection is a necessity. 



It has been demonstrated by recent experiments that it is- 

 possible to secure by selection a great improvement in the 

 uniformity of the rubber stand. It is equally possible to obtain a 

 considerable increase in yield, and the planter should give the 

 closest attention to these and other points which can be controlled 

 by careful selection. The planter should first decide upon the type 

 of tree he desires and when he has formed a clear conception of this 

 in his mind he should go through the rubber forest, carefully 

 observing the trees and selecting the number of trees he needs for 

 the production of his seeds. When these seeds have been collected 

 and treated in the best possible way, they should be further selected 

 by the screen and the common specific gravity methods. When 

 such seeds have germinated the resulting seedlings will clearly 

 demonstrate the benefit of seed selection. As soon as the young 

 plants have reached a height of 7 to 8 inches it is time for the planter 

 to pass through his fields, eliminating all plants that are defective^ 

 backward, or in any other way undesirable. 



Increased Size and Productiveness. 



Only a superficial observation is necessary to show the planter 

 that when a rubber tree is cultivated properly it re-acts to good 

 treatment. If the trees have good soil with sufficient moisture, 

 plenty of light and air, and no crowding or competition with other 

 plants of its own or any other kind, it will grow quicker, remain 

 healthier and more robust, and what is most important, it will 

 furnish a greater surface for tapping, than if exposed to the 

 vicissitudes of the natural struggle for life in the forest or in a 

 plantation where the trees stand too close. 



If we subject the trees to the best possible treatment according 

 to modern and improved methods of silviculture we will soon be 

 repaid for the additional care bestowed upon the plants. There 

 can be no doubt but that the size of the trunk can be considerably 

 increased by breeding and selection. There can be as little 

 uncertainty in regard to the possibility of increasing the amount of 



