crops which are cultivated from June to September should be 

 grown on ridges or ridging done after the plants are a foot or 

 two high. Sowing in trenches is advisable in the dry 

 weather and so ridging should be done, specially in clay soils, 

 for dry weather crops also. Ridging facilitates sowing in 

 lines and using of hoes. The ridges can be split or spread 

 out with the double-mould-board plough or a Hunter hoe 



FIG. 3. THE HUNTER HOE. 



- 3 ) an d the soil levelled, as in the case of sugarcane, 

 potatoes, ground-nuts, mulberry and other crops which are 

 benefited by subsequent earthing. The splitting of ridges after 

 the plants are sufficiently high, acts like manuring. Sour and 

 boggy soils are particularly benefited by ridging, as free 

 access of Oxygen reduces the organic acids and converts 

 sulphides into sulphates. Neither nitrites nor nitrates can 

 exist in the black non-aerated stiff and damp clay until the 

 soil '<is exposed to the action of air which is best done by 

 ridging. The yellow Ferrous silicate of non-aerated soils also 

 changes into red ferric silicate by [ridging. Ridging or 

 splitting of ridges" thus serves the following purposes : (a) 

 Covering, say potatoes, (b) preventing water-logging, (c) sup- 

 porting maize, sugarcane and other tall crops and preventing 

 their lodging, (d] manuring a growing crop with properly 

 nitrified and aerated soil- (e) correcting acidity and poisons 

 by aerification and (/) earthing. 



128. Subsoiling. The use of mould-boards for plough- 

 ing is of great importance as they invert the soil, thus 



