A work unit to be attached to a lower side of a work vehicle that includes a wheel includes a work portion, a housing that covers the work portion, a bridge portion that is provided above the housing, auxiliary plates that change their positions between a state of being housed in the bridge portion and a state of protruding from the bridge portion, a linkage mechanism that is provided in the bridge portion and is connected to the auxiliary plates, and an operation tool for operating the linkage mechanism. As a result of operating the operation tool, the linkage mechanism is folded or unfolded, and positions of the auxiliary plates are changed between the state of being housed in the bridge portion and the state of protruding from the bridge portion.
