120 THE RUBBER TREE BOOK 



trees widely planted might not be equally successful, yet surely 

 one might reckon that they would obtain, in a fair measure, 

 the same results. 



If the results obtained were only one-fourth as good as 

 those obtained on Pangkattan Estate, they would still be three 

 times as good as those obtained on an ordinary plantation. 



There would, in addition, be further substantial advantages. 

 These trees having a healthy development denied to closely- 

 planted trees, would, as a matter of certainty, have a longevity 

 denied to closely-planted trees, thus making the rubber planta- 

 tion more of the nature of a permanent investment. 



Further, with only forty-eight trees to tap per acre, instead 

 of, say, one hundred and fifty, the costs of tapping, of tools 

 and of utensils would be considerably less. This is a matter 

 not to be overlooked. Days of low prices may come, and such 

 things as this may be important factors. 



With only forty-eight trees to the acre each individual 

 tree could receive an attention impossible with, say, one hundred 

 and fifty trees to the acre. To plant out forty-eight trees to 

 the acre should cost a little less than one hundred and fifty 

 trees. To manure the young plants should certainly cost less 

 with forty-eight trees than with one hundred and fifty, and this 

 good start in life might thus come more readily within the means 

 of the planter. 



It is of course not contended that all estates will give the 

 same results. There are estates at too high elevations, estates 

 with sandy soils, and estates with too low a rainfall. Yet, 

 wherever cultivation is possible, it will be found to improve the 

 growth of the trees, and light and air are necessary to rubber 

 wherever it is grown. As the result of cultivation one estate 

 in Sumatra had a yield of over 1250 Ibs. per acre from its oldest 

 rubber, which is quite in excess of yields generally obtained and 

 points to what can be done. 



In certain countries and certain districts dry, hot winds 

 prevail at certain seasons and not only greatly retard the growth 

 of the trees, but almost entirely arrest for the time being the 

 process of carbon assimilation by the leaves. This, of course, 

 means, for the time, a stoppage of food-supplies and throws 

 the tree back on its reserve stores of food-supplies. The reason 

 of this is that the continued winds dry up the film of moisture 



