PROBLEM TO BE SOLVED: To certainly and smoothly carry out a returning motion of a ridge edge clutch after operating to cut off the ridge edge clutch having a function to stop at a predetermined position in a power transmission structure of a seedling planting device which is constituted to drive a planting mechanism through the ridge edge clutch constituted to be a claw clutch having the function to stop at the predetermined position and operated to cut off the clutch in a predetermined range in planting claw acting phases. SOLUTION: A planting clutch comprising a claw clutch having the function to stop at the predetermined position is installed in upstream of a transmission of the ridge edge clutch. A phase for beginning to cut off the clutch of the planting clutch is brought to be delayed to a phase for beginning to cut the clutch of the ridge edge clutch. COPYRIGHT: (C)2003,JPO