A grass treatment unit with an adjustable hood for use with various grass treatment inserts of different diameter for verticutting, scarifying, etc. An open topped bearing socket is provided for mounting the grass treatment insert for rotation. A hood is mounted on a slide for spacing the hood in a selected position with respect to the grass treatment insert. The grass treatment insert has a shaft with ball bearings on opposite ends which are housed within a bearing housing. A handle is provided on the bearing housing for lifting the grass treatment insert.