What’s the difference between pruning a tree and topping it?

severely topped tree
A radical topping has ruined this tree. Photo: City of Olympia

What’s the difference between topping a tree and pruning it? When major tree limbs are severely and haphazardly cut, the tree is permanently damaged—the tree has been topped. When tree limbs are carefully cut, the tree continues to thrive and be beautiful—that’s pruning.

Here’s a video from the US Forest Service and DNR about tree topping.

DNR’s Washington State Urban and Community Forestry Program says that when a tree is topped and many major branches are removed, the tree literally can starve to death. The cutting upsets the balance between the tree’s leafy crown and the amount of its roots. The imbalance seriously affects the tree’s food supply. A lot of leaf surface is needed to take in light and carbon dioxide to produce sufficient food for the branches, trunks, and roots. Topping cuts off a major portion of the tree’s food-making potential, and also severely depletes the tree’s stored energy reserves.

After topping, many suckers (epicormic shoots) sprout from dormant buds along the older trunk or branches of a tree. These shoots develop quickly as weakly attached branches, growing in response to the massive stress to the tree. Large branch stubs and big wounds left from topping seldom close or heal completely. Nutrients are no longer transported to the large stubs, and the large, open cuts are vulnerable to insect invasion and fungal decay. Once decay has begun in a branch stub, it may spread into the main trunk. Also, the exposed wood often rots, causing weak, hollow limbs. Consequently, previously topped trees often have dead or dying limbs that need to be removed.

As a result of all this, the weak, hollow limbs and decay increase the risk of breaking, with potential damage to people or property. 

Topping trees actually can cost more in the long run than proper pruningFrom the visual aspect, topping disfigures the tree. Unsightly branch stubs, obvious pruning cuts, and a broom-like branch growth replace the tree’s natural beauty and form. In contrast, when carefully pruned, the shape and health of the tree are maintained or enhanced—and well- pruned trees likely will need pruning less often.

Topped tree
The 'broom look' of this willow was caused by severely topping the tree--wrecking its future growth. Photo: Linden Mead/DNR

 If you are considering pruning or cutting down trees in your yard, and you don’t have the experience or training to do it correctly and safely, contact a local certified arborist. An arborist can give you great advice on what’s best for your tree.

Visit treesaregood.org for information and to find an arborist in your area.

DNR’s arborists work with cities and Urban and Community Forestry Programs to help them grow a bounty of healthy, beautiful trees in the communities across Washington State.