11 



CULTIVATION, DRAINAGE AND MANURING. 



By F. G. Spring, n.i>.a., f.l.s. 



(Agriculturist, F.M.8.) 



FN the past fcAV years many changes and improvements have been 

 made in rubber planting but this is only what would have been 

 expected considering the size and importance of the industry. It 

 cannot be claimed, however, that there has been any gi^eat advance- 

 ment in knowledge of soil culture and artificial fertilizers as applied 

 to rubber land. The varying conditions under which a I'ubber tree 

 can be grown are partly responsible for the somewliat slow progress. 

 Hilly and Hat lands should not be treated in all respects alike and the 

 same applies to heavy and light soils, deep and shallow. 



The objects of tillage are to make the soil lighter, more porous 

 and permeable to roots, to enable vegetable and mineral matter to 

 decompose more rapidly, to promote oxidation and stimulate the 

 activity of nitrifying bacteria, to loosen the particles of soil and mix 

 them, to check the growth of Aveeds and reduce soil evaporation. 



Soil Cultivation and Drainage. 

 Tillage is of the utmost imj^ortance but it requires to be applied 

 to suit conditions. Heavy yields of rubber are obtained, in many 

 instances, on land which has never been tilled and svhich is com- 

 paratively poor in essential plant food constituents but in- such cases 

 it is generally found that the mechanical condition or mixture of the 

 soil is excellent. Rich lands are sometimes very poor yielders and this 

 may be owing to quite a variety of causes but a not uncommon one is 

 mixture of soil. The mechanical condition of a soil is of the greatest 

 importance in rubber growing, more so, perhaps, than its chemical. 

 Improvements can be effected in this direction by tillage and the 

 turning under of green manures, the latter opens up heavy soils and 

 renders light soils heavier, or in other words tetids to establish an 

 equilibrium, 



i will deal in the tirst place with hill cultivation and then refer 

 to treatment of undulating and tlat lands. It is common knowledge 

 that tillage cannot be carried out on hill land without considerable 

 loss by surface wash, but several methods may be adopted to enable 

 one to cultivate a soil properly and yet reduce surface wash to a 

 minimum. A cover-crop on the land is a reliable preventative, but, 

 unfortunately, there is always a period of soil svash following tillage 

 even with a plant which rapidly reproduces itself. 



Terracing has much in its favour but can only be recommended 

 provided it is done previous to planting. The terraces require to be 



