The practice of topping is so widespread that many people believe it is the proper way to prune trees.  It's not, for a variety of practical and aesthetic reasons.

Topping can cause a variety of problems in trees, and ultimately cause problems for homeowners.

Topping is the excessive and arbitrary removal of all parts of the tree above and beyond a certain height with no regard for the structure or growth pattern of the tree. 

Pruning is the selective removal of certain limbs based on the structure and growth pattern of the tree.

• The tree is too tall - This indicates either poor species selection, improper tree placement, or fear that the tree might be dangerous in storms.

• Topping reduces the risk of storm damage - The reduction in height reduces risk temporarily, but as the tree regrows it is structurally weaker and the risk becomes greater.

• It has to be topped because of power lines - Tree and power line conflicts may be resolved by proper species selection, better placement or different pruning technique.  Remember: power line clearance benefits the lines, not the trees.

• The balance between the roots and crown is destroyed.  Removal of too many branches and leaves can starve trees.  Without foliage trees cannot make enough food to maintain growth and vigor.

• Sunscald can occur.  Bark tissues suddenly exposed to full sun may be burned and develop disease cankers.

• Large stubs can't heal.  Stubs are separated from food and water flow.  As tissues die, wounds don't seal, and decay may enter and spread to the trunk.

• New growth is weak.  New sprouts are attached to the surface of stubs rather than being anchored from within former limbs.

• Topping can create a hazard.  Storms do more damage because the new growth is weakly attached.

• Topping disfigures trees.  Topping alters trees' natural beauty and form.

• Topping is only temporary.  Trees will grow to their natural height.  Rapid regrowth is nature's way of recovering from disasters, and frequent topping will be required to keep a tree under control.

Select the right tree and plant it in the right place.  A tremendous selection of trees is available.  One can be found that will grow to just the right size.  Avoid power lines and other hazards.

Remove the tree and replace it.  If removed, then follow the right tree in the right place guidelines.

Prune the tree properly.  Proper pruning removes limbs where they are attached to a larger branch or the trunk.  Selective removal of limbs reduces the wind resistance of the tree.  It also allows some light to penetrate the crown.  Proper pruning improves the shape and balance of the crown.

The practice of topping is not recommended.  It can lead to decay, storm damage, and disfigured trees.  Proper pruning that thins the crown, with cuts made at branch collars, is the best practice for the long term health of trees.