Professional Tree Trimming Process

1. Remove Lowest Branches:

   This can be done gradually as the tree grows. If this is not done, these branches have a greater potential for failure as the tree ages. If they do fail, the damage can ruin the tree. These lowest branches also are the ones that cause interferences with streets, sidewalks or routine maintenance such as mowing. Also, removing them accelerates tree growth as energy is diverted to growth at upper levels.

   The height of these branches does not increase as the tree grows. The only increase in height for trees occurs at the top and tips of branches each year.

2. Try To Maintain A Central Leader For The First 10 To 15 Feet:

   Inspect for co-dominant stems. These are stems competing to be the central leader. Choose the strongest and straightest and trim out the competing one or ones. The sooner this is corrected the greater control over the shape of the tree will be.

3. Broken or Diseased Branches:

   Prune out any of these types that are apparent

4. Always Make Proper Branch Collar Cuts:

   When making your final cut on each branch, make it on the outside edge of the branch collar. Cutting too close to the parent stem is flush cutting. Cutting too far away is stub cutting. Both of these cuts are detrimental to tree health.

   The branch collar contains natural tree defense chemicals which protects the tree. If it is removed, the amount of tree decay is increased at the site and the structural integrity of the tree is decreased. If stubs are left, proper closure is hampered and food and shelter source is left for potentially harmful insects or decay fungi.

5. Thinning And Branch Separation

   Some branches growing in the center can be removed. Rubbing or crossover branches can be removed. Too many branches growing close together vertically up the trunk can be removed to increase the vertical distance between these branches (branch separation). This type of thinning also increases the speed of height increase for the tree and, properly done, improves the form.

6. Suckers

   If any suckers are growing at the base of the tree, they can be removed. If this is done in late summer, it will reduce re-suckering.

7. Tree Trimming Dosage

   Young trees recover faster and easier than mature trees from trimming. Generally up to 30 percent of the crown can be safely removed.

   A ratio of two-thirds crown to one-third stem is recommended for an aesthetic overall balance.

8. Tree Wound Dressing

   Tree wound dressings are no longer recommended. They have been proven to be detrimental to tree health. Inevitably, decay pockets are increased, which is a drain on tree energy reserves and the structural integrity of the tree is compromised.

9. Tree topping:

   Trimming branches at the top (removing the upper crown) is not an acceptable tree trimming method (unless the upper portion is deadwood or declining). It adversely affects the health and longevity of trees. It causes a profusion of weakly attached branches at the top and destroys the natural form.

10. Horizontal Branches vs. Acute Angle Branches:

    Horizontal branches are structurally stronger than acute angle branches. Wherever a choice can be made between them, while maintaining the integrity of the natural tree form, favor the horizontal branches and remove the acute-angled branch.

Trimming Mature Trees

As trees age, the recommended amount of live wood trimming decreases. Mature and over-mature trees generally do not have as much stored energy reserves to counteract the effects of trimming. Live wood, which is necessary for photosynthesis production, is more important to retain for the health of trees. Current recommendation for live wood removal on older trees is 0-10 percent.

As with younger trees, dead wood removal is recommended for tree health improvement. Removal of broken branches or hazardous branches is always recommended.