If you have a new or young tree in your parkway or on your property, keep it healthy by watering it during dry periods. New trees need about one inch of rain per week to become established. If they do not receive this rain, provide a deep soak by gently running the hose at the base of the tree for about an hour. Maintaining a ring of mulch around the base of the tree two to three inches deep will keep the soil moist longer. However, do not pile or place mulch against the trunk of the tree; this will cause the bark to rot and decay, which will eventually kill the tree.