PROBLEM TO BE SOLVED: To provide a planting arm of a seedling planting device in which a weight of the planting arm is reduced and cost is reduced.SOLUTION: A planting claw 25 is connected to a support case 36, and a seedling extrusion tool 26 is supported to the support case 36 along the planting claw 25 in a reciprocating manner. A spring 29 for biasing the seedling extrusion tool 26 in the side projecting from the support case 36 and a drive mechanism 31 for drawing the extrusion tool 26 into the support case 36 against the spring 29 are provided in the inside of the support case 36. A lid part 37 is provided to be connected to the support case 36 for supporting the end of the spring 29 on a portion opposite to the planting claw 25 in the support case 36. The lid part 37 is formed of a synthetic resin while inserting a nut 50 for mounting a grease nipple to the lid part 37.SELECTED DRAWING: Figure 5
