Comparing penetrometer and shear vane measurements with measured and predicted mouldboard plough draught in a range of Swedish soils

▶ Soil strength proved much more sensitive to changes in water content than draught requirement. ▶ Draught requirement better correlated to cohesion than to soil penetration resistance. ▶ Strong correlation between draught requirement and clay content. ▶ Model calculations overestimated draught requirement.