Abstract
The research was carried out at Hummaidat township 15km west of Mosul city to investigate the effect of disk angle (35ْ,42ْ,and 48ْ) of the vertical disk plow with three plowing speeds (4.86,7.24 and 9.30)km/hr on number of masses exceeded 10 cm/m2, bulk density, porosity, effective plowing depth, coefficient of working width, slippage percentage, field efficiency, effective field capacity, pulling force, drawbar power and the power lost due to slippage. Results showed that the effect of interaction between disk angle and plowing speeds was significant in bulk density and power lost due to slippage while there were no significant differences concerning other studied characteristics. The disk angle 42o showed higher significance in the effective plowing depth, coefficient of working width, bulk density and porosity .
