When the branches of a large tree become heavy and start distorting the natural shape of the tree, the tree must be thinned. When we thin the crown of any tree, we achieve additional air flow, increase light penetrations (which allows grass to grow beneath the tree), and it also helps in retain the natural shape of tree while reducing heavy weight on limbs.
When we see branches on a tree that are dead, dying, diseased or weak, we must remove them. Crown thinning also entails removing limbs that rub together or against other trees or objects and removes selected suckers and branches through the inside of the tree. We'll also remove selected branches in crowded parts of the canopy (or crown). This creates a lacier visual effect. We do all this to reduce diseases, molds and fungi.