Tree Trimming vs. Pruning: What’s the Difference?

For larger branches, cut back to just above where a smaller stem emerges from the branch you are pruning (lateral branch). For smaller branches, cut back to an outward-facing bud. 

When cutting branches over 1-1/2 inches in diameter, use a pruning saw or bow saw to make a 3-part cut:

1. Make the first cut from underneath about 6 to 12 inches from the trunk. Cut about 1/3 of the way through the branch. 

2. Next, cut 3 inches away from the first cut towards the end of the branch. As you are making the cut, the branch will fall, so you may need to

    support it to prevent tearing.

3. Finally, the remaining stem back to the branch collar.

DO NOT apply wound sealer to the cut; it only slows healing, promotes decay, and leaves your tree vulnerable to disease. 

Trimming Techniques

The same cutting techniques apply to trimming and shaping your trees, hedges, and shrubs that you use when pruning. 

Always cut at a 45-degree angle and never below a bud or into the collar of a branch. 

How to trim stems. Image courtesy of Almanac.

When trimming a hedge, use guides and cut using sweeping upward motions. Remove inner branches to thin out the center to promote light penetration and airflow. Cut the sides at an angle so the base is wider than the top. 

For tips on hedge trimming, read Hedge Trimming: You Asked We Answered.

Can I prune or trim too much? 

You can prune or trim your tree too much. Removing more than 1/3 of your tree’s canopy (tree topping or heading) in a given year can kill your trees. For young and newly planted trees, do not remove more than 25% of their canopy in a year. The canopy is where the majority of growth happens. Removing it stops growth, weakens your tree, and leaves it vulnerable to insects, windthrow, and disease. 

Do I prune mature trees differently than young trees? 

Mature trees can handle more aggressive pruning than young and newly planted trees. While you can prune up to 1/3 of the canopy on a mature tree in a given year, you should never remove more than 25% of a young tree’s branches during a pruning season. 

When pruning young trees, you aim to ensure it develops a robust root system and structure. You will remove branches to prevent trunk splitting and sail branch growth while encouraging the development of a healthy, uniform canopy. 

Read How To Prune Young Trees For Structure And Form for more tips on pruning young trees. 

When pruning mature trees, you focus on maintaining their shape, structural integrity and improving leaf, flower, and fruit production. 

How do I prune and trim fruit and flowering trees? 

Fruit-producing and flowering trees require pruning to encourage blossoming and quality fruit production. While you can trim many tree species throughout the growing season, you should avoid trimming away dead branches until after flowering trees have finished blooming. 

It is safe to cut away dead, dying, broken, damaged, and diseased branches during dormancy. 

PRO TIP: Some flowering trees produce new growth and blossoms from dead wood. We recommend consulting with a local arborist or tree service with extensive knowledge of pruning and trimming flowering trees and shrubs before getting out the shears. 

What about pruning and trimming hedges? Is there a wrong way to do it?

Like other trees and shrubs, hedges should be pruned during dormant periods. How to correctly prune and trim your hedge depends on whether it’s for privacy or ornamental purposes and what type of plants make up your hedge. Different trees have different growth rates and maintenance needs. 

For example, evergreen hedges require little to no pruning, while deciduous trees and mixed hedges require pruning every few years and regular trimming to promote the desired growth and keep their shape. Flowering hedges require more specialized care. 

While hedge-trimming techniques are straightforward, knowing when and how to prune them correctly requires the right tools, knowledge, and experience. 

You can over-prune your hedge, which leads to premature death. Pruning so the top is wider than the base prevents sunlight and moisture from reaching the bottom branches, resulting in a lush green hedge at the top and a thin, dead base. 

To ensure your hedges get the maintenance they need, hire a professional. 

What if my tree is near utility lines or very close to my house? 

If your tree is near utility lines or very close to your house or other structures, have a professional take care of the pruning and trimming. Falling branches and debris can damage nearby structures or fall on power lines. Local arborists and tree care companies have the tools and skills to groom trees in any location safely. 

PRO TIP: If you need to trim or prune trees near utilities, in alleys, or the right-of-way, the city will cut them for free. They may not make them look pretty, but they get the job done. 

Can I trim and prune the parts of the tree that are on my neighbor’s property? 

If the tree trunk is on your property, you are responsible for pruning, trimming, and caring for your tree. You can remove or trim overhanging branches beyond your property line without violating trespassing laws. 

If you need to prune or trim a tree that overhangs your neighbor’s property, contact them and come to an agreement on how best to approach it. If you plan to hire a professional service, notify them so your neighbor knows what to expect and when. 

Open communication can alleviate conflict and stress when caring for trees that grow on your and your neighbor’s property. To learn more about where the responsibility for shared trees lies, read our blogpost regarding timber trespass. 

What if my tree is infested with insects? 

If you suspect your tree is infested with insects, contact your city or a local arborist before attempting to trim or prune it. They can help you identify what type of pests are damaging your tree- invasive or native - and take appropriate measures to contain and control them. 

For information about Washington invasive pests and what to do if you see them on your trees, go to https://invasivespecies.wa.gov/. 

What if I see fungus or strange growths on my tree? Can I cut them off? 

If you see fungus or other odd growths on the trunk or branches of your tree, contact a certified arborist or tree service near you. They can determine the safest, most effective course of action and whether removal is necessary. 

Do not attempt to cut off or disturb the fungus. Doing so will cause it to release spores into the air and spread to other trees and plants. 

For information about tree diseases common in Seattle, read Common Tree Diseases To Watch Out For In Your Seattle Trees or visit https://www.seattle.gov/trees/tree-pests/disease-pests. 

How do I remove large branches? 

Apply the 3-Part Rule  when removing large branches. Use a saw and have someone help you to ensure the branch is supported to prevent tearing or damage when it falls. We recommend having a professional remove large branches that cannot be safely removed from the ground or if the tree is close to structures, utilities, or public spaces.