White Oak Has Black Round Lumps On Leaves

Question From: MARYLAND
Q: Our white oak tree has round lumps on some of the leaves that look like dried cranberies but are black. They are clustered. When then dry and fall off they flatten on the driveway they look like dried drops of tar. What is this?


Your tree has a fungal disease. Due to the unusually hot, dry weather trees are very stressed and the fungal disease in just one of its problems. I recommend you have a certified arborist, a trained tree doctor do an onsite inspection of you oak tree and other trees and shrubs on your grounds. Best And Happy Yardening, Nancy.