TILLAGE 



667 



land, sandy land from clay land. Rubbish on the surface 

 may be handled by one plow and not by another. On 

 wet clay one should use a different shape of plow f rom 

 that which is preferable for dry soil. 



FIG. 68. The plow. (1), modern walking plow with parts named; 

 (2), types of moldboard for (a) fallow ground, light soil, (6) fallow 

 ground, clay soil, (c) sod ground, (d) general purpose, fairly well 

 suited to a wide range of soil conditions ; (3), deep-tilling disk plow ; 

 (4) , subsoiler ; (5) , plow attachments : (a) jointer, (6) knife or 

 beam colter, (c) fin colter, (d) rolling colter. 



572. Shapes of moldboard plows. Of the moldboard 

 type there are two general shapes : (1) The long, sloping 

 moldboard, which rises very gradually and has little or 



