254 THE RUBBER TREE BOOK 



spread the more widespread are the available sources of supply. 

 Stiff, uncultivated soils hinder such free expansion of the roots 

 as is eminently desirable for the welfare of the tree. So does 

 close-planting. Manuring freely does not make up for this want 

 of room. No matter how much plant-food there is, it can only 

 be absorbed in a state of solution. The policy of close-planting 

 and freely manuring advocated by a well-known planter seems 

 thus based on a misunderstanding of the conditions of plant life. 



The rainfall varies in many districts in a most surprising 

 manner. In the case of neighbouring plantations, one estate 

 often seems unduly favoured and the other neglected. In 

 times of drought, when rain is very much needed, it is galling 

 to see showers pouring over neighbouring estates and ceasing 

 just at the edge of one's own plantation. Yet this is a common 

 occurrence on many estates. 



Rainfall returns should be most carefully kept, and the 

 records for past years should be always available. These are a 

 useful guide to estate managers, informing them of the months 

 in which a good rainfall can be reasonably expected, and in what 

 months rainfall is scant and precarious. The prudent manager 

 will not set about his planting-out during the months v/hen a 

 sufficient supply of rain is doubtful. 



Where an estate has any inter-crops planted, or where it 

 is proposed to plant inter-crops, the rainfall records should be 

 first consulted. On certain estates in East Java, for example, 

 one sees certain estates with cacao as an inter-crop. Had the 

 rainfall records been first consulted, a wise manager would not 

 have planted cacao on these estates. The rainfall is insufficient, 

 and sometimes it is unseasonable. Hence some of these estates 

 have never had a really good crop of cacao. 



Eighty inches per annum is about the smallest amount con- 

 sistent with the welfare of a rubber plantation. Ten inches 

 more rainfall are a very valuable asset, and other 10 or 20 inches 

 still better. Light, porous soils and a scanty rainfall mean 

 poorly-grown rubber and small returns of latex. Heavy, clay 

 soils withstand droughts longer and better, but need more 

 tillage. 



Where the surface of the soil is caked and hard the greater 

 portion of the heavy showers of rain flows off immediately into 

 the drains and is lost. In such a case a rainfall of 80 inches per 



