SEEDER CULTIVATORS 



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primarily for seeding purposes are also cultivators, 

 and their use is equivalent to a cultivation. The grain 

 drill is a good example of this group. It is essentially a 

 cultivator either shoe or disc adapted to depositing 

 the grain in the soil at the proper depth. All types of 

 planters which deposit the grain in the soil have a similar 

 action on the structure of the soil. The ordinary two- 

 row maize planter, the potato planter, etc., while of 

 low efficiency, as cultivators, still have an effect which 



Fig. 144. Grain drill with either hoes or discs, and having 

 fertilizer-spreading attachment. 



is measureable. This action is well seen in the lister, 

 used for planting maize, by which the grain is deposited 

 beneath the furrow, which is filled by cultivation after 

 the grain is up. The lister is generally used without 

 previously plowing the ground, and its use is limited 

 to regions of low rainfall where the soil is aerated by 

 natural processes. Lately, plowed ground listers have 

 been introduced, which combine the advantages of deep 

 planting with proper preparation of the soil. 



There is also a very considerable tillage action in 



