PLANTING AND CULTIVATING. 43 



accruing from frequently harrowing or cultivating the land 

 between the trees. This operation not only checks the growth 

 of weeds but breaks up the surface crust which forms after rain, 

 thereby facilitating the ingress of air. During the dry season 

 the layer of dry, loose soil thus formed serves as a blanket to con- 

 serve the moisture in the soil beneath. It is inadvisable to stir 

 the soil too deeply during the dry season, as evaporation is greater 

 from the cultivated than from the uncultivated soil, and a shallow 

 layer of dry soil is almost as effective as a deep one for moisture 

 conservation purposes. It may appear contradictory, but the 

 same conditions which most favour the retention and conservation 

 of rain water also best facilitate the draining away of surplus 

 water. A loose soil absorbs more water than a compact soil, and 

 surplus water drains away far more rapidly from soils in the first 

 than from those in the second condition. However satisfactory 

 the climatic conditions or the composition of the soil may be, 

 unless the physical condition of the soil be suitable the best 

 results will not be obtained. 



Due care must, of course, be exercised in regulating the 

 length of the teeth of the harrow or cultivator to prevent injury 

 to the roots of the trees. Where, as frequently happens, the 

 roots have formed a network near the surface of the ground close 

 to the trunks of the trees, operations should be suspended in 

 these areas and mulching applied in the shape of weeds, leaves, 

 or, preferably, stable litter. 



Drainage is necessary to improve the sanitary condition of 

 the soil and promote the formation of soluble plant-food 

 constituents. 



Drains on hill slopes check the washing away of rich surface 

 soil, and in such situations small drains at fairly frequent 

 intervals are preferable to large drains widely distributed. 



DISBUDDING AND PRUNING. 



There is a vast difference in the habit of Hevea trees ; some 

 will commence to branch when they have grown 6 feet high, 

 while others will grow more than 20 feet high before branching. 

 Later on it will be shown that it is considered desirable to 

 encourage the girth development of the 7 or 8 feet of the trunk 



