43 ROT ATI OX OF CROPS 



land, after the crop has been harvested. The cropping being 

 stopped, a rest is provided for the soil, during which a new supply 

 of plant-food becomes stored up, and this becomes available 

 for the succeeding crop. For the more permanent crops, however, 

 such as Tea, Cocoa, Coconuts, and Rubber, fallowing cannot 

 obviously be adopted, and manuring and tillage operations must 

 then be relied upon to meet the requirements of the crops grown. 

 Leaving the ground fallow for a certain period has also the bene- 

 ficial effect of ridding the soil of fungi or insects pests. 



ROTATION OF CROPS 



Plants differ, as shown by their ash, in the relative proportions 

 of plant-food they require and obtain from the soil. Therefore 

 when successive crops of one kind are grown on the same ground, 

 those elements which are most consumed obviously become 

 exhausted. Consequently the soil becomes "poor" or unproduc- 

 tive, the crop weak and sickly, and even the application of costly 

 manures does not satisfactorily restore fertility. The principle 

 of cropping by rotation is to avoid this, by preventing two crops 

 of the same kind succeeding each other. The advantage of 

 the system is undoubted, and in some temperate countries its 



PLANET JUNIOR CULTIVATOR. 



adoption is usually made a compulsory rule in the farmer's lease. In 

 the tropics, however, rotation is often impracticable, owing to the fact 

 that many of the crops grown are of a perennial nature and, once 

 planted, last from a few to a great many years. But wherever 

 possible, as in the case of garden or annual crops, (root-crops, 

 grains, pineapples, and vegetables) as well as tiowering-plants, the 



