the potato diggers are made to dig one row of potatoes or other root crop. The machines can be pulled on the centerline of the tractor or offset as when straddling two rows and digging one. The standard diggers return the produce onto the dug soil after shaking the bulk of the soil through the chain. The soil type and produce size dictate what pitch of chain is needed. The hydraulic drive allows better matching of chain speed with digging conditions.