Ash dieback—Botryosphaeria stevensii or Diplodia mutila
Ash dieback is a fungal disease primarily affecting Raywood ash. Leaves fade, turning yellow or brown, eventually wilting. Symptoms are often scattered throughout the canopy. Branches die. The entire plant may die.
There is no known specific remedy for controlling ash dieback. Provide a good growing environment and appropriate cultural care.
Raywood ash leaves dying from ash dieback
Limb cankers on Raywood ash