Written by: Marge Vorndam, Master Gardener Emeritus
Introduction/Purpose
Many folks, including the author, know that pruning residential trees is important for reasons presented below. But we may not have the understanding or experience to tackle this activity ourselves. By researching and writing this article, I hope to give us the knowledge why this process is important in landscapes and other places that would benefit from this practice. In my case, I have a Honey Locust copse along the front of my home in Rye which has never been pruned and desperately needs attention.
Foremost, the purpose of pruning is to increase the aesthetics of ornamental trees by directing new growth and increasing the ornamental beauty of trees in their landscapes. Pruned trees add value to real estate and create a framework which augments ambiance. Pruning also increases the safety of the surroundings where dead or damaged trees could impact a home or similar structures.
In this article, we will address the considerations and processes of pruning mature and young shade trees. Different methods are needed when addressing fruit trees, flowering/non-flowering ornamental bushes, vines, roses and fruit bearing trees and evergreens and will not be covered here.
Objectives
Pruning removes damaged and decayed branch sections and improves the overall health of ornamental and shade trees. The technique opens the tree structure to allow more sun and air to penetrate the tree canopy, promoting a more balanced growth pattern for the entire tree. Here is an example of how pruning can benefit a tree. Note how the tree branches are thinned out, giving the pruned tree an airy, open look.
From Family Tree Service
https://www.familytreeserviceinc.com/
Used by verbal permission of business owner, 5/13/2025.
When to Prune
Timing is important. Avoid pruning actively growing trees, if possible. This will restrict timing of most pruning activity to dormant trees in the late winter before leaf and flower budding occurs. This period would include the months of January, February, and very early March here in Pueblo. Ideally, trees will heal the pruning cuts by sealing off the open wounds from insect and microbe damage before budding-out occurs. Due to the increased potential for further damage from pathogens and pests, the removal of any dead, diseased and damaged wood should be removed when it is discovered rather than waiting until winter.
Keep pruning activity to a level that will still sustain the tree growth. No more than a maximum of 20% to 30% of a young, established tree’s branches should be removed annually per the seasonal growth period. Mature trees should only have up to 10% removed annually. More than that amount can affect tree growth and health overall. Do not prune newly planted trees until roots have developed, usually after two-three years.
Pruning Equipment
Items needed for pruning include gloves, ladder, disinfectant, protective equipment, wheelbarrow or cart. The appropriate cutting tools for the work at hand are necessary also:
These primary tools are used to trim out /thin branches up to ¼ inch in diameter. Lopping shears can be used on longer branches up to 2” diameter. For larger diameter branches over approximately 1/2”, be sure to check out the section below on the appropriate cutting method to use to avoid damaging the wood remaining inside of the cut on the tree.
For larger branches that are higher up in the tree, consider using these types of pruners.
Larger diameter branches that are closer to the ground can be cleared with a pruning saw.
Illustrations fr. Texas A&M University, https://aggie-horticulture.tamu.edu/earthkind/landscape/proper-pruning-techniques/
Chainsaws are useful on thicker branches, but caution and appropriate experience are needed. It may be wise to have a certified arborist with the skills to handle pruning if resorting to use of a chainsaw. The rule of thumb is to not cut out branches that are more than 3” in diameter unless the branches present a structural issue – such as would occur if the tree had two leader branches at the apex.
Methods
Don protective gear – goggles, ear and eye protection if using power tools, clothing with arm and leg covering, gloves and stout footwear. A head covering, such as a hard hat, and a well-supported ladder are especially useful when working on branches above your head. Begin by cleaning equipment to prevent cross-contamination of diseases from previously trimmed trees. Using a spray bottle of bleach diluted by water, or rubbing alcohol, is a good option to maintain sanitary tools. Sharpen tools to enhance safety of use.
Trim young shade trees to set the stage for a well-formed mature tree. Don’t cut out temporary branches at bottom of a young tree until the tree is two to four years old. For all trees, branches to focus on are dead, dying, diseased or damaged branches. These can be removed any time of the year. For spring pruning, remove inward growing branches, tangled branches that are crossing each other or at weird angles. Target water sprouts and suckers. These branches are thin and weakly attached, growing upright off a tree trunk or larger branch. Cut out one rubbing branch. Take out one of the double leaders at the top of a tree.
Fr. University of Maryland extension. 2025. https://extension.umd.edu/resource/pruning-trees-home-landscape/
Appropriate pruning cuts to use for branch size are important to know. The right pruning cut for the branch attachment situation are essential to protect the tree bark still on the tree. See CSU GardenNotes #612 for more information on this important topic. Removal Cuts, Reduction Cuts, Heading Cuts, Thinning Cuts, Three Cut and Jam Cuts are all specialized for different types of pruning situations. They should be appropriately used, depending on the pruning situation.
CSU GardenNotes #611 covers Tree Growth and Decay – essential information for any Arborist to know.
CSU GardenNotes #613 examines Structural Training of Young Shade Trees.
CSU GardenNotes #615 explains further some of the concepts presented here about Pruning Mature Shade Trees.
Which Branches to Prune: Pruning Young Shade Trees – The Basics. Trees. Charlotte. https://www.youtube.com/watch?v=HAZLSkV7dRI
Results
The value of pruning can be reiterated by viewing a well-pruned tree. Its structure is pleasing to the eye in landscape settings and creates a healthier tree in the process.
Note examples of good pruning practices and poorly accomplished pruning results if trimming is done poorly. Which tree would you rather have in your landscape?
These illustrations are an example that show how proper and improper tree pruning can affect a tree shape. Illustrations are taken from Texas A&M University, https://aggie-horticulture.tamu.edu/earthkind/landscape/proper-pruning-techniques/
Discussion
This article is a brief presentation about managing trees to create healthy and aesthetically beneficial green (or other colors found in trees) structure on your property. Hopefully, it has provided information about this less familiar topic related to your property care and how to improve its appearance.
If you are still reluctant to take on the effort of pruning yourself, or your tree is tall, you might consider engaging the services of a qualified trained arborist. This person can address the task of handling more complicated forms of pruning that you don’t want to tackle yourself or help you to know how to keep your tree pruned into the future. Never attempt to prune trees near powerlines or in other hazardous environments yourself.
Ask your local horticultural agent/Master Gardener group for recommendations. Call the Master Gardener Help Desk at 719-583-4628 or search on Find an Arborist for your locale.
References
CMG Garden Notes, 2024. #611, #612, #613, #615. Master Gardener. Colorado State University Extension. Web citations are provided above.
Fazio, James R. How to Prune Young Shade Trees, Bulletin 1. Arbor Day Foundation, 211 N. 12th Street, Lincoln, NE 68508. Arborday.org. https://www.arborday.org/tree-resources/how-prune-young-shade-trees
USDA, NACD, Arbor Day Foundation. Prune Your Trees. Bulletin 9. Arbor Day Foundation, 211 N. 12th Street, Lincoln, NE 68508. Arborday.org. https://www.arborday.org/tree-resources/prune-your-trees
Welsh, D. & J. Everett. 2008. Follow Proper Pruning Techniques. Earth -Kind Landscaping. TX A&M AgriLife Extension. Texas A&M University System. Horticulture/Forest Science Building | 2134 TAMU | College Station, TX 77843.
https://aggie-horticulture.tamu.edu/earthkind/landscape/proper-pruning-techniques/