A harrow is a farm implement used for surface tillage. It is used after ploughing for breaking up and smoothingout the surface of the soil. The purpose of harrowing is to break up clods and to provide a soil structure, calledtilth, that is suitable for planting seeds. RICOITALY 7X7 Trailed Disc Harrow trails behind the tractor and because of heavy design and weight can effectively break up heavy clods.