I planted a river birch cluster this spring. Four trunks about 6 feet high....
I planted a river birch cluster this spring. Four trunks about 6 feet high. The lower leaves recently began to turn yellow and bottom leaves are falling off. More leaves are turning yellow. I don't see insects. What could it be? I am south of Hudson-not sure of the county
In Spring we had plenty of rain so the birches leafed out in EXCESS. Now that the days are getting warmer, too much leaf surface has been produced and as a result, the birches defoliate. If the green leaves are on the tips of the branches and the yellowing leaves are nearest to the trunk or lower on other branches, not to worry.