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Daily Archives: October 27, 2021

Creating Company Culture – TCIA Podcast Featuring Jeff & Amy Grewe

We’re honored to be featured in the latest TCIA Podcast talking about all things company culture, marriage and business partnerships, how COVID impacted our industry, and our experience in becoming a TCIA Accredited company! Check it out!

Listen to Podcast

Did you miss our previous article…

Arbor Anesthetics – Innovative Pain Management Solutions for Tree Pruning

We’re revolutionizing the tree trimming industry! Introducing Arbor Anesthetics – the new technology that allows us to humanely trim your trees. Now you can rest assured – your tree will feel absolutely no pain during the limb removal process! Isn’t it time we treated our trees with more respect?
APRIL FOOLS! But all joking aside, there is a right and a wrong way to trim a tree. Every cut is a wound. Trimming a tree correctly leverages a tree’s own recovery system, which walls off decay and prevents the spread of disease. 

Here are FIVE ways you can prevent harm to your trees:

  1. Flush Cuts – Improper Pruning Techniques
  2. Mulch – but not too much!
  3. Will cutting into a tree’s roots harm the tree?
  4. DIY Tree Pruning
  5. Tree Topping Hurts

​Don’t fool around with your trees! Hire a professional, Certified Arborist, like Arbor Aesthetics Tree Service!

Flush Cuts – Improper Tree Trimming Techniques


Tree trimming is an essential component of tree care in an urban setting. Limbs need to be removed over streets and sidewalks, away from roofs and gutters, or even in the yard if the homeowner needs to be able to walk under the tree. Removing these limbs may seem straightforward, and one might be tempted to remove them in such a way that it appears the limb never existed, by way of cutting it completely flush with the trunk. This is what we call a “flush cut” and it is an improper pruning technique that can cause serious harm to your tree. 

Trees have a response to wounding, coined “Compartmentalization of Decay in Trees” or “CODIT.” A tree “walls” off decay in four layers of bark tissue, preventing decay from moving vertically, radially and tangentially. When a wound occurs naturally, the tree gets to work using its own defense mechanism to keep decay-causing fungi from spreading. When a wound occurs during routine tree pruning (yes – it’s a still a wound!), a trained arborist can take steps to ensure the tree is given its best shot at using its CODIT system.

Maintaining the branch collar is critical in tree pruning and allows the tree to form a proper callus around the wound. The illustration to the right shows a clear swelling of tissue at the branch collar as the tree is preparing to shed a dead limb naturally. Trees know what they’re doing! When we prune live limbs, we can use this as a model for where to make our cut – by not cutting into the branch collar. The branch bark ridge is not always obvious, and when it is not easy to identify the collar, we consider it best practice to come away from the trunk slightly. It would be better to leave more of a stub than it would be to cut into the branch collar. 

In general (and certainly not in all cases), a proper pruning cut will result in a circular wound or as close to a circle as possible. In the photos, you can see the elliptical shape of the cut where the flush cut was made parallel to the trunk, but not perpendicular to the branch, resulting in a vertical ellipse where we can see the branch collar was removed. 

If you are unsure where you make a proper pruning cut, it’s best to consult a certified arborist. You can read more about DIY Pruning in a previous blog post.


  • Compartmentalization of Decay in Trees, Bartlett Tree Experts
  • University of Iowa Extension & Outreach