Bacterial leaf scorch, also known as Marginal leaf burn, is a chronic and systemic disease mostly affecting oaks and maples. This fatal condition is sometimes mistaken for Oak wilt or Dutch elm disease, or drought and heat stress. There is no cure.
Bacterial leaf scorch is most often found in pin oak, red oak, shingle oak, and white oak. It is also found in elm, mulberry, pecan, red maple, sugar maple, and sycamore.
What causes Bacterial leaf scorch? Bacterial leaf scorch is a relatively new disease thought to be caused by the bacterium Xylella fastidiosa. The bacteria invade the xylem tissues of the plant, restricting the flow of water from the roots to the crown. Symptoms include premature browning and leaf drop. This condition progressively worsens over a period of three to eight years.
Professional, laboratory diagnosis is the only way to confirm this disease. There is no cure for bacterial leaf scorch.
Trunk injections of antibiotics, proper irrigation, and mulching may reduce symptoms and slow disease progression. Pruning diseased tree branches has not proven effective.