125 



plough, or a special moulding-up implement, is used. 

 In wet seasons it is often very difficult to get the- 

 moulding-up performed at the proper time, as it is 

 important that the land shall be in a dry condition,, 

 otherwise the earth is plastered down firmly about the 

 stems, and if dry weather follows it sets hard, and the 

 formation of the tubers is interfered with. If the 

 operation is delayed too long, some of the roots are 

 destroyed, and those tubers which are forming near 

 the outside of the ridge, become exposed when they 



MOULDING-UP PLOUGH. FIG. III. 



increase in size, causing them to become green and of 

 less value. As a rule, early varieties need not be so 

 thoroughly moulded as is required for the main crop 

 varieties, but the thoroughness of the moulding has a 

 great effect on the degree of disease which affects the 

 tubers. Deep moulding undoubtedly prevents, to some 

 extent, the loss occasioned by disease. The formation 

 of the ridge is somewhat regulated by the soil and 

 climate. In districts where the rainfall is usually 

 light, especially where the soil is of a very open 

 nature, it is important that the rain should be conducted 

 to the ridge, so that the plants may fully benefit by it. 



