I Pruned a Birch Tree Recently and the Branches Are Bleeding Profusely. Why?
Birches and a number of other tree species, including ornamental and fruiting cherries, will drain lots of sap if they are pruned in late winter or spring. There’s nothing that can be done to stop it once the flow has begun. Painting the cut with sticky “wound paint” isn’t effective and isn’t recommended by Washington State University plant specialists. The flow usually stops. Trees with this characteristic are best pruned in fall or very early winter before the sap begins moving.
