A stacking head for stacking rolls of sod can include a number of screw assemblies that are employed to secure and remove sod rolls from a stacking conveyor. Each screw assembly can include a center stake and a corkscrew that pierce a roll as the stacking head is forced into the roll. The rate at which the stacking head is moved vertically relative to the roll can be synchronized with the rate at which each screw assembly is rotated. This synchronization ensures that the corkscrew will pass into the roll while the stacking head is simultaneously forced into the roll without damaging the delicate sod.