The most important thing to consider when pruning a tree is the timing. If you make pruning cuts at the wrong time, even if they are good cuts that avoid the most common mistakes, you risk leaving your plants and trees vulnerable to airborne pathogens and insect-borne diseases. Pruning when the tree is producing new flowers and leaf buds can force the tree to use some of its stored energy to produce replacement buds. It is essential to consider the final height of the mature tree before planting it, as coverage often occurs when a tree grows beyond its allocated space.
When a branch is cut, the tree develops a special callus tissue along the lines of a scar that covers the wound to prevent decay and disease. A stem cut can leave too much of a dead branch on the tree, which will decompose backwards through the center of the root neck and into the trunk. Removing excess foliage and branches from a young tree can help to boost its natural growth, increase its yield, and make it more structurally sound. Trees are naturally flexible and have withstood weather conditions for centuries, but a tree with a lion's tail has lost its protective and flexible shape and can be more easily damaged in winter. Lion's tail pruning is not an alternative to cleaning or reducing tree crowns, and it should never be done by an unqualified tree pruner. When a tree is pruned heavily during the growing season (spring to late summer), there is a risk that it will starve due to too many leaves being removed.
Pruning large branches, with diameters greater than 3 or 4 inches, can create wounds that are too large for the tree to seal. The removal of healthy branches should only be done during the dormant period in mid-winter, when the tree is essentially asleep, or in spring when it has just started actively growing again and new growth is forming naturally.
