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out shade. Windbreaks will very likely be necessary everywhere 

 in these islands. As the native forest does not produce sufficient 

 shelter, wind belts of Grci'illca or Albizzia should be ])lanted. It 

 may be found advisable to plant Albizzia nwluccana between the 

 rubber trees and keep them pruned down so that the rubber at 

 an age of two years will outreach the tops. In that manner the 

 Albizzia would be covering the ground and at the same time sup- 

 plying green manure to the soil. 



In planting Hevca seeds in the nursery it is a good plan to add 

 to the soil a mixture of cattle manure and leaf mold, in which 

 case a much improved growth would be apparent. In Ceylon 

 the young seedlings are attacked by a number of enemies such as 

 rats, hares, etc. To keep these animals away the young plants 

 are often enclosed in rabbit wire netting. When rabbit netting 

 is used for individual plants they are surrounded by a circle of 

 netting, about 6 to 9 inches from the plant and of a height of 

 three or more feet. In making holes for the final planting of 

 these seedlings it is a good plan to give the plant plenty of room. 

 The larger the holes the better, as the Hcvea is a very greedy 

 feeder. 



It is a well known fact that the Hcvea does not necessarily re- 

 quire a very rich soil. This refers also to other rubber trees 

 with the exception of Ficiis. The main requirements as regards 

 soil is good drainage and deep soil with sufficient subterranean 

 water supply. It may be found that the Hawaiian soils are rather 

 too acid and require liming. The question of fertilizing the soil 

 for rubber is as yet unsettled as very few experiments have been 

 made. When the cover of Para trees is once established the soil 

 will keep on improving on account of the action of the roots and 

 the natural accumulation of leaf mold. Green manure has been 

 tried and the plants respond readily. 



The superiority of Hcvca above other rubber producing trees 

 has been amply demonstrated in Ceylon. This tree is compara- 

 tively hardy and permits a system of tapping which invariably 

 would destroy both Castilla and Manihot. The multiple tapping 

 which is practiced on Hevea gives ultimately a considerably larger 

 amount of rubber per tree than can be obtained from any other 

 plant. From that point of view cultivation of Hez'ca is the most 

 profitable. Tapping Hcvca is, however, connected with much 

 work and where labor is expensive this tapping becomes a serious 

 item. In comparison the tapping of Castilla is cheap, because it 



