THE EFFECT OF SOIL COMPACTION ON MOLE PLOW DRAFT

Conventional and zero traffic systems were mole ploughed and effects o n soil physical properties were compared. Draught of the plough operat ing at 550 mm depth was measured while it was winched across plots hav ing a 5-year history of different traffic regimes. Results showed that the draught was reduced by about 18% on non-trafficked compared with conventionally-trafficked soil. Cone resistance measurements, 1 month before and 3 months after mole ploughing, confirmed that the non-traff icked soil had significantly less strength to a depth of about 400 mm. Bulk density measured at 75 and 175 mm depth 1 month before mole plou ghing indicated a similar trend, but clod and bulk densities at 125 mm and 350 mm depth 3 months later, failed to show any consistent differ ences between treatments.