The caterpillar damaged the leaves of the apple tree, will this affect the harvest?

Even if there are few caterpillars, they can still destroy the crop. They very quickly destroy the leaves of the entire tree. Caterpillars usually attack in the spring. Precisely at a time when there is still no fruit. And without leaves, photosynthesis, normal metabolism cannot occur. There will be no apple harvest if caterpillars attack the leaves. In the worst cases, the tree can die if it does not have enough substances obtained during photosynthesis. Therefore, you need to process trees and protect them from parasites, if they live in your area.