Abstract: Apparatus for eradicating tree stumps comprising a rotary cylinder or drum having knives or teeth around its periphery. The teeth include both cutter teeth and chipper teeth. The primary purpose of the chipper teeth is to hog out and remove the fibrous wood material. The primary purpose of the cutter teeth is to break up and cut or slit the fibers so that they may be more easily hogged out by the chipper teeth.

Abstract: Apparatus for eradicating tree stumps comprising a rotary cylinder or drum having knives or cutters around its periphery. The cutters are mounted on rings which encircle the drum. The rings have circumferentially spaced mounting surfaces which are staggered relative to one another so that the cutters when secured to the mounting surfaces are themselves staggered for more effective cutting action. The drum is supported by two rotary hydraulic and/or electric motors having aligned output shafts which are connected to the ends of the drum to support and also to rotate it. The motors are carried by the arms of a yoke. Instead of two motors, there may be a motor at one end of the drum and a bearing at the other.