Abstract: A vegetation cutter is mounted on the end of an articulated boom supported for horizontal and vertical movement on a relatively small tractor by removable frame means. The frame means includes front to rear extending left and right longitudinal side frames which are connected by a U-shaped frame extending over the motor housing of the tractor and connected at its lower end portions to the side of the frame members. A rotary vegetation cutting housing is pivotally attached to the outer end of the articulated boom by a unique linkage means permitting the housing to be pivoted about a horizontal pivot through an arc in excess of 180.degree.. A hydraulic motor on the cutter housing drives a cutter blade through a unique non-tapered cutter shaft which is held in the housing in the event of bearing seizure by unique drive means which precludes the rotating blade from dropping from the housing to create an accident hazard.