Structural Pruning
Most shade trees evolved in the forest, they grew straight and tall because there was fierce
competition for light. When we plant them in areas with an abundance of light, trees tend to grow
multiple trunks, excessively large or long lateral branches and often have too many branches
originating from one point on the trunk, all of which contribute to weak structure. The goal of
structural pruning is to mimic the form we see in nature. A single dominant trunk and evenly spaced
branches form strong structure, thus a healthier long lived tree.
Structural pruning should be performed every 3 to 5 years, for the first 25 years of a trees life.
Most shade trees evolved in the forest, they grew straight and tall because there was fierce
competition for light. When we plant them in areas with an abundance of light, trees tend to grow
multiple trunks, excessively large or long lateral branches and often have too many branches
originating from one point on the trunk, all of which contribute to weak structure. The goal of
structural pruning is to mimic the form we see in nature. A single dominant trunk and evenly spaced
branches form strong structure, thus a healthier long lived tree.
Structural pruning should be performed every 3 to 5 years, for the first 25 years of a trees life.
Thinning
Thinning the canopy allows more light to penetrate to the center of the tree. This increases the
growth interior foliage, increasing trunk diameter, strengthening the interior structure of the tree. It
also improves airflow, reducing likelihood of disease and storm damage.
Thinning the canopy allows more light to penetrate to the center of the tree. This increases the
growth interior foliage, increasing trunk diameter, strengthening the interior structure of the tree. It
also improves airflow, reducing likelihood of disease and storm damage.
Canopy Reduction
Sometimes a tree grows too big for it's space. The best way to avoid this is proper plant selection,
however it's often preferable to perform a reduction rather than removal and replacement. When a
reduction is performed branches are cut back to a lateral which is big enough to assume apical
dominance over the branch. While this is typically not good for the tree, it is often the best available
option, far better than topping or heading cuts.
Sometimes a tree grows too big for it's space. The best way to avoid this is proper plant selection,
however it's often preferable to perform a reduction rather than removal and replacement. When a
reduction is performed branches are cut back to a lateral which is big enough to assume apical
dominance over the branch. While this is typically not good for the tree, it is often the best available
option, far better than topping or heading cuts.
Crown Cleaning
Crown cleaning is simply removing dead, dying, broken defective and diseased limbs from the tree.
This removes pathogens from the area, reducing the spread of disease. It also reduces hazards to
people and property below or around the tree.
Crown cleaning is simply removing dead, dying, broken defective and diseased limbs from the tree.
This removes pathogens from the area, reducing the spread of disease. It also reduces hazards to
people and property below or around the tree.
Lifting the Canopy
Lifting is the removal of lower branches to provide clearance for people, vehicles or structures. Over
lifting is harmful to the tree, as it removes foliage, reducing the energy producing ability of the tree.
However, procrastinating will allow the branches that must be removed eventually to grow large,
resulting in large pruning wounds which are potentially harmful to the tree. Lifting the canopy slowly
over time will be best for the health of your tree, while also satisfying your needs.
Lifting is the removal of lower branches to provide clearance for people, vehicles or structures. Over
lifting is harmful to the tree, as it removes foliage, reducing the energy producing ability of the tree.
However, procrastinating will allow the branches that must be removed eventually to grow large,
resulting in large pruning wounds which are potentially harmful to the tree. Lifting the canopy slowly
over time will be best for the health of your tree, while also satisfying your needs.
A common misconception is that pruning should only be performed at certain times of year. On most
trees light pruning can be performed at any time. If heavy pruning is necessary it's best to avoid
pruning during the spring growth flush. During this time excessive sprouting can occur, bark and
cambium are easily damaged and the tree's energy reserves are at their lowest point. Once the
leaves have hardened and turned dark green heavy pruning will be less stressful. One exception to
this general rule are fruit trees. Because fireblight is a common problem in our region it is
recommended that most fruit trees only be pruned when dormant (November to March).
trees light pruning can be performed at any time. If heavy pruning is necessary it's best to avoid
pruning during the spring growth flush. During this time excessive sprouting can occur, bark and
cambium are easily damaged and the tree's energy reserves are at their lowest point. Once the
leaves have hardened and turned dark green heavy pruning will be less stressful. One exception to
this general rule are fruit trees. Because fireblight is a common problem in our region it is
recommended that most fruit trees only be pruned when dormant (November to March).
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Tree & Shrub Pruning
Why Prune Trees?
There are many reasons why we prune trees, which include:
There are many reasons why we prune trees, which include:
- Reduce hazards to people and property
- Maintain the health of the tree
- Encourage strong structure
- Decrease damage potential from snow and wind loads
- Enhance beauty
- Reduce shade or wind resistance
- Provide clearance for pathways or structures
Improper Pruning Harms Trees
The following practices harm trees:
The following practices harm trees:
Topped tree in
Broomfield, CO
Broomfield, CO
Proper Pruning Techniques
When to Prune