Sunscald
Sunscald
Common name
Sunscald
Southwest injury
Causal agent
Sunscald is a physiological disorder primarily seen in thin-barked trees. During winters, the northern wood trees are exposed to direct sunlight on their southwest side. This awakes the trees from their dormancy. When night falls, and the temperature drops significantly, the active bark cells die due to extreme temperatures.
Symptoms & Signs
The scalded area of the bark shows discoloration, sinks inside, and may fall off, displaying dead tissues of the cambium. This opening gives way to many pathogens that can enter and cause further damage to the trees. Leaves also show signs of scalding by withering and dried leaves. Fruits, especially ripened, also develop wrinkled patches, which turn soft on the exposed side. The exposed area turns white and gives rise to the growth of fungal colonies.
Time of concern
Winter and early spring
Common hosts
Maple
Sweetgum
Ash
Apple
Mango
Citrus