Leaf scorch is a noninfectious condition caused by an unfavorable environment - there is no virus, no fungus, no bacterium. It can not be helped by chemical control so you will have to discover the underlying causal factor which can be drying winds, drought, root damage and other environmental problems.

Still, infectious diseases can attack the tree and make their condition even worse. Major trees susceptible to leaf scorch are Japanese maple (plus several other maple species), dogwood, beech, horse chestnut, ash, oak and linden.

• Common Non-infectious Tree Diseases

Japanese Maple Leaf Scorch - Steve Nix Photo, Licensed to About.com