Too much of anything can be a bad thing. Just like humans, too much sun can be bad for trees, as well. Sounds silly, right? We all know trees need sunlight to grow and thrive, but too much sunlight can actually harm a tree.
A tree can get a “sunburn” just like you; there’s potential for the sun to cause permanent damage or even death in a tree. When a tree receives too much sunlight, it can develop sunscald. Sunscald damages the outer layer of the tree. A tree can develop spots and lesions, which can allow for other diseases to enter the tree. The bark, leaves, and fruit can be affected by too much sun. If a tree is really damaged by sunscald, the bark is affected to the point that the inner tissues of the tree are exposed. At this stage, it may not be possible for the tree to heal and survive.
Young trees and trees with thinner bark are more prone to getting sunscald. Sunscald makes it easier for fungi, bacteria, and insects to infest a tree. If a tree can no longer protect itself from such outside forces, the tree will decline, get sick, and even possibly die. There is no way to reverse sunscald, so your best bet is to prevent it from happening.