DeWitt dew right slow release tree watering Donut is designed for newly planted trees & shrubs. it is designed to provide a drip irrigation system directly to tree & shrub roots over an extended period of time. Using the Donut takes the stress out of planting new trees. The watering Donut is designed to ensure that your new trees will survive their crucial first year after being planted. it eliminates the severe water stress new trees endure after transplanting by delivering a high volume of water directly to their root system.