“Kind pruning is not just a matter of the size of the cut, nor even how the plant looks after pruning. The true test of success is ‘are you retaining the long-term health and beauty of the plant?’” - Cass Turnbull
At first glance, pruning seems like an easy task: you grab your hand pruners or loppers and go to town, right?
Not so fast.
If done properly, pruning will help maintain the health and beauty of your trees and shrubs, but if done hastily, it can cause irreversible damage.
Here are some common mistakes to avoid:
Pruning without a goal
Pruning should achieve a particular goal (for example: removing dead limbs or increasing fruit or flower production) without sacrificing the overall health of the plant. Pruning without a goal causes damage to a tree or shrub for no reason at all. Extensive improper pruning at best takes time and patience to fix, and at worst causes harm that cannot be reversed. So think before you cut!
Improper pruning cut
A proper pruning cut minimizes the damage done to the tree and allows it to heal quickly. An improper cut like a flush cut (cutting too close to the trunk) or a stub cut (cutting too far from the trunk) can cause irreversible damage to a tree. A flush cut removes the branch collar and leaves a large wound in the side of the tree that won’t heal properly. A stub cut leaves too much of a dead branch on the tree which will decay backward through the center of the root collar and into the trunk of the tree. Both of these damaging cuts result in decay, which could lead to death.
Heavy pruning during the growing season
When a tree is heavily pruned during the growing season (spring until late summer), there is a risk of starving the tree by removing too many leaves. (Remember: leaves are how trees make their food.) Summer is also the most likely time for a drought to occur; a tree that is already stressed from over-pruning will be less resilient when water is scarce. Removing too many branches can also cause bark that has always been shaded to be exposed to the hot, fierce sun. This will create sunscald, which hurts the plant.
Using dull tools
Dull tools might not seem like a big issue (because really, who even thinks to sharpen their pruners or loppers?) but they can cause significant damage to a tree. Pruning with unsharpened tools can create rough or improper cuts that rip or shred the bark, causing larger wounds.
Topping a tree
Topping a tree is precisely what it sounds like – cutting off the top of a tree. This practice causes undue stress to trees and can unbalance the structure of the tree, making it more likely to fall. Topping happens most often when a tree grows out of the space it was allotted, which is why it’s so important to consider the eventual height of the mature tree before you plant it.
Over-pruning any time of year
It is especially important to avoid over-pruning during the growing season, but over-pruning any time year can stress a tree, making it more susceptible to disease. It’s important to remember that every pruning cut matters because every cut is a wound to the tree. Removing branches takes away stored resources, impacts future growth, and reduces the tree’s photosynthetic capacity. Worse yet, pruning creates entry points for wood-decay fungi to enter the tree and begin rotting it from the inside. One too many poor pruning cuts can result in the death of a tree.
If pruning is harmful to a tree, why prune at all? Though pruning may cause harm, it often creates long-term benefits that outweigh the immediate damage, including:
- Increased safety
- Increased health
- Increased beauty
If you keep these benefits in mind and avoid these six common mistakes, you’ll be well on your way to becoming a proper pruner.
Have a pruning question or problem that has got you stumped? Send us a message and we will be happy to find the answer for you!