Preliminary testing determined how the tractor responded to on-the-go gear changes under load while being cautious of engine overloading when operating in higher gears. The gears selected
based on the preliminary testing were 2nd (approx. 3.0 km/h) for the slow treatment, 5th (approx. 5.8 km/h) for normal, and 8th (approx. 8.3 km/h) for fast. The targeted nominal tillage depth was 30 cm and was preset prior to initiating this study. Actual depth of tillage was evaluated by extracting the soil disrupted by a shank and measuring the distance from the soil surface to the bottom of the disrupted area. This depth was measured at one location within each plot. Once the tractor was aligned with the plot, the MFWD and axle differential lock were engaged with the tractor engine set to full throttle. The implement was then lowered to the preset depth initiating a pass