An apparatus for processing plant material comprises a cylindrical drum 10 that is rotatable about a drum axis, a rotary drive 12 for rotating the drum about the drum axis, and a curved shell 20 that extends around at least part of the circumference of the drum. A processing channel 22 is defined by the outer surface of the cylindrical drum and an inner surface of the shell, said processing channel having an inlet end 22a and an outlet end 22b. The drum has on its outer surface a first set of working elements 16 and the shell has on its inner surface a second set of working elements 30, said first and second sets of working elements being configured to process the plant material as it is fed through the processing channel. Also disclosed is the apparatus being included with a harvesting mechanism, a baler and a loader wagon.
