In a device for working ground surfaces or roadways including a machine frame and a working drum in a drum housing arranged at said machine frame, where no less than one spraying device extending parallel to the working drum and featuring several outlet nozzles for spraying agents arranged next to one another and directed towards the working drum is arranged at the drum housing, where the outlet nozzles include one each drivable closing mechanism with a closing element which, in an open position, fully uncovers the nozzle channel of the outlet nozzle and, in a closed position, closes the nozzle channel, it is provided for the following features to be achieved: that a controller drives the closing mechanisms, with the outlet nozzles and the related closing elements being adapted to one another in such a fashion that the flow cross-section in the outlet nozzle is variable in accordance with the position of the closing element on a specified path between the open position and closed position.