287 



Reduced to 1 M 2 of tapped surface, then tree No. 14 seems to be 

 a better rubber-producer than tree No. 9. 



No. 14 gave, rather should have given, 1334 and No. 9, 850 

 grammes of rubber per M 2 of tapped surface. 



The individual differences in the product of latex given by the 

 above methods of tapping are clearly shewn by the results of the 

 first year's tapping of two 24-year old trees growing next to each 

 other and tapped at the same time and by the same methods. 



Tree No. 10 was tapped over a surface of 4*5 M 2 and tree No. 

 11 of 3*35 M> 



The yield was, respectively, 380 and 608 grammes or 84*4 and 

 1 8 1 *5 grammes per M 2 - 



Tree No. II yielded more than twice the quantity of rubber, not- 

 withstanding that the other was tapped over greater surface. 



From these experiments we may conclude that there exists a great 

 deal of individual difference in the yield of rubber amongst the trees 

 cultivated in the Gardens. 



These trees are also different in their forms. The best rubber 

 producer is compact, has a thick crown and leaves of which the 

 length and breadth are nearly equal, while the crown of the other is 

 wider and the leaves are longer. 



In the first year of tapping, the influence of the season is also 

 apparent. 



Tree No. 2 was tapped in August (the dry season) and again in 

 November. The yield was, respectively, 411 and 390 grammes per 

 2*79 M 2 of tapped surface or per M 2 » respectively, 147*3 and 139*8 

 grammes. 



This shews that the difference in this case was not large. It may 

 be noted that the East Monsoon was drier than the West Monsoon 

 but not much, however, as may be seen from the Rain-tables. 



In the dry season there were, during the time of tapping, 6 rainy 

 days with 148 m.m. of rain, while during the wet season, these figures 

 were 13 and 165. 



If the humidity of the soil is large * and if the rains are equally 

 distributed during the tapping season, then there ought to be no 

 large difference between the yield of the wet and dry seasons, t 



We shall have the opportunity of following these results for con- 

 secutive years. From the above results, we may also reduce that 

 full grown trees may, according to our system, be tapped twice a 

 year. 



The second year will shew how far an increase of the number of 

 incisions increases the yield of the rubber. 



* In our case we have to deal with clayey soil. 



f Large differences are caused in cases where factors that cause drying, such as a 

 clear sky, much sun and wind, are acting during the tapping. Of this, we have been 

 s able to amply satisfy ourselves, and for that reason the trees are tapped as early as 

 possible in the morning and tapping is not continued longer than till lo a, Mi 



