n8 THE RUBBER TREE BOOK 



same may be said of air; while it will be obvious that the less 

 the soil preserves of a tree are encroached upon by neighbours, 

 the greater will be the stores of plant-food at its disposal to 

 draw upon. But the most important factor of tree vitality 

 yet remains to be indicated, namely, moisture. In the Tropics 

 fertility follows in the track of the rain ; and one of the functions 

 of rain is to keep the water-table at its normal level. It is 

 not unlikely that this large and vigorous Hevea may have 

 succeeded in tapping subterranean reservoirs, as yet out of 

 reach of its companions. Now, if this is so, and had this 

 tree been subjected to systematic manuring, root development 

 might have been encouraged towards the surface instead of 

 towards the deeper layers of the soil, and in that case the water- 

 table might never have been reached. We have here then a 

 hypothetical case, and it seems to me not at all an unreasonable 

 one, in which manuring might actually have done harm instead 

 of good. You cannot, of course, argue from one tree, especially 

 a tree that is a generation older than most rubber trees on the 

 island. I have only taken it to illustrate the point I wish 

 particularly to make, which is that, in the presence of natural 

 forces working so very much more vigorously than we have 

 been accustomed to in temperate climates, where the science of 

 agriculture has been built up, it is possible we may be devoting 

 too much attention to what I will term the artificial side of 

 rubber cultivation manuring and methods of tapping and 

 that we might achieve better results at first by devoting our 

 energies more to removing obstacles from the path of Nature 

 and giving her rein. We should endeavour to secure, as far 

 as we can, that Nature has full scope for the use of her vast 

 resources with each individual tree in the plantation, and that 

 each individual tree is given full play for the utmost exercise of 

 its functions. After that we may begin cautiously to offer her 

 assistance with such puny means as we have at our disposal, 

 being ever watchful that, instead of helping her, we may not 

 be hampering her." 



Mr Lyne's observations are very much to the point, and it 

 would be well if more of the gentlemen with some training in 

 the sciences in the service of the various Governments preached 

 from the same text. He seems, however, to ignore the essential 

 part filled by the microscopic soil flora in relation to soil fertility. 



