To eliminate the need of replacing a marker body frequently, in a marker device for forming an index in a farm field.SOLUTION: A marker device 33 includes a shaft member 55A and a marker body 51. The marker body 51 includes: a connection part 52 connected to the shaft member 55A so as to be rotatable； and a marking part 54 provided around a rotation axis P1 of the connection part 52. A bushing 56 is interposed between the shaft member 55A and the connection part 52.SELECTED DRAWING: Figure 5【課題】圃場に指標を形成するマーカ装置において、マーカ本体を頻繁に交換しなくてもよいようにする。【解決手段】マーカ装置３３において、軸部材５５Ａとマーカ本体５１とを備える。マーカ本体５１は、軸部材５５Ａと回転可能に連結される連結部５２、連結部５２の回転軸Ｐ１まわりに設けられたマーキング部５４を備える。軸部材５５Ａと連結部５２との間に、ブッシュ５６を介在させる。【選択図】図５
