Abstract: The invention is directed to a method and apparatus for comminuting stumps. The apparatus includes a generally cylindrical stationary drum having a feed opening in the upper portion through which stumps are fed to the drum. A rotatable substantially horizontal bottom encloses the lower end of the drum and is disposed to rotate about a vertical axis so that the stumps are forced to the outer periphery of the drum under centrifugal force and revolve along with the bottom. An abutment or counter member extending upwardly from the bottom and the stumps are braced against the countermember as they are moved into engagement with a generally cured vertically disposed blade that is spaced inwardly of the drum. The blade acts to comminute the stump and the chips or particles are discharged from the drum through a discharge opening which is disposed radially outward of the blade.