A wheeled chassis to which a stump grinding unit is securely attached that includes a chip collector attached to either the stump grinder or the wheeled chassis and positioned adjacent the trailing edge of the stump grinding wheel. The wheeled chassis includes a duct in fluid communication with the chip collector, and a collection bin positioned adjacent the trailing end and in spaced relation below the duct. The wheeled chassis is adapted for hitched connection to a vehicle. A blower can be positioned within the duct to produce a rearwardly directed air flow to assist in the chip movement towards the collection bin. The collection bin can be positioned on the wheeled chassis or on a vehicle to which the wheeled chassis is attached.