River Birch – Trunks Catching and Holding Water
Q: Nineteen years ago I planted three Heritage river birch trees. They have multiple trunks. Two of them have a “crotch” between the trunks that fills with water when it rains. Will this ultimately lead to rot and the death of the tree? Can I create an “umbrella” to reroute the rainfall?
A: There is no need to do anything. In my experience, these depressions rarely cause damage to the bottom of the tree. If water pools there for several days in summer you might have a mosquito problem, but that’s all. Put a B.t. mosquito dunk, available at nurseries in the low spot.
Do not drill a drain hole in the tree…this will certainly cause more problems than it solves.