Abstract
The experiment was carried out at Agriculture Collage - University of Tikreet during the agricultural winter season 2009 in Gypsfreous soil .Three plowing speeds included 2.5, 4.5 and 6.5 km /h with three cover height angles of rotary plow included 25, 45 and 65 degree to evaluate it's effect on some Gypsfreous soil physical properties included Bulk Density, Porosity , Percentage of soil clods which diameters are less thin 5 cm / m2 and Soil penetration resistance in this study. Complete randomized block design (RCBD) with three replications was used in this experiment and Duncan was used to comparison the mean of treatments.
The results obtained reveals that plowing speed 2.5 km /h bulk density reduction and gaves the largest porosity and gaves soil penetration resistance reduction and Percentage of soil clods increased. While, gaves cover height angle 65° less bulk density and largest porosity . The cover height angle 25° gaves largest Percentage of soil clods and less Soil penetration resistance .
The results obtained reveals that first plowing speed 2.5 km /h with cover height angle 65° gaves less bulk density and largest porosity, While, the plowing speed 2.5 km /h with cover height angle 25° gaves largest Percentage of soil clods and less Soil penetration resistance .