The study has been conducted in AL-Azaizya city (AL-Kut GovernorateK ,
80 km south-east Baghdad . To evaluate the field performance of mould
board plough. Two evaluations are considered in this regard; first adding
or not adding water to the driving tires of tractor, while the second
evaluation includes three levels of ploughing depthes (10, 15 and 20 cm).
The random complete block design (RCBD) was used in the statistical
analysis of obtained data, which are based on the observations of three
replications. The results have demonstrated that adding water to the
driving tire of tractor is significantly effective in decreasing the number of
soil granules masses that have a diameter of more than 10 cm (from 7.3
mass/m2 to 3.4 mass/m2). Equally important, increasing tillage depth from
10 cm to 15 cm and then to 20 cm also caused an increase in the number of
soil granules masses from 4.4 mass/m2 to 5.2 mass/m2 and then to 6.6
mass/m2, respectively. Adding water to driving tires of tractor causes a
reduction in slippage percentage from 12.9% to 8.5%. In contrast,
increasing tillage depth causes an increase in the slippage percentage from
9.7% to 10.6% and then to 11.8%. Finally, the practical production is
decreased due to the added water to the driving tires and rising the tillage