Deborah maple is producing heavy sap on all its leaves. It has never done this before. Is it most likely because of bacteria, or sickness in the tree?
Certified GKH Gardening Expert
Unfortunately it is a bug infestation. The sap is actually honeydew, which several different pests secrete, such as aphids or scale. I would treat the plant with neem oil. Neem oil is very effective on these kinds of pests and is safe for people and pests. This article may help: