Young trees put on growth during spring and will often sprout new buds and side shoots where you don’t want them. Sides-hoots on trunks, for example, are not wanted and energy expended on growing them could be better expended further up the tree.
For this reason, during Spring maintenance, the unwanted growth is gently removed. Its one of those tasks where the hands alone are the best tool as one can apply the right amount of pressure to rub off the young shoots.
This is how its done: