Abstract: There is disclosed herein a mobile material shearing apparatus for receiving solid waste material and reducing said material to a comparatively small size. The apparatus includes an elongated movable truck bed on which is mounted a rotary shear into which the solid waste material is fed for size reduction. The smaller solid waste material exits the rotary shear and is received on a conveyor which delivers the material either to a predetermined location for disposal without further processing or to a rotary classificaton mechanism for further processing. The classifier receives the sheared solid waste material and separates particles which are above and below a predetermined size. A discharge is provided for receiving the smaller particles (fines) and means are provided for returning the larger particles (overs) to the shear for further size reduction.