Affixed at the base of newly planted or small trees (or shrubs), Tree Watering Bags are designed to slowly leak water from release points on the underside to provide a constant source of moisture where needed most: the roots. Available in two styles, vertical- or ring-type, the bags are made of durable, UV-resistant material, ensuring their repeated use. The verticals are usually used for trees up to 4 inches diameter, the ring-type for up to 8-inch-diameter trees. Capacities vary from 15 to 32 gallon and drip times from a few days to one month via emitters provided.