A cutting assembly for a header of a plant-cutting machine includes a blade assembly fastened to a head assembly, which is configured to be drivingly connected to a motor. The cutting assembly is suitable for mounting proximate to the center of the header, in an end-to-end relation with another cutting assembly. Removal of the blade assembly from the head assembly can be efficiently effected by releasing or removing a small number of fasteners, thus allowing an operator to readily remove or replace the blade assembly as needed.