When is the best time to prune a tree?
- When your saw is sharp.
- After a branch smacks you in the head.
- Anytime is fine.
Fall and winter.
Pruning trees when they are dormant is the best for them for two reasons. First, the dormant season is when deciduous trees have lost their leaves and stored all of the energy that those leaves made during the summer. By removing limbs at this time we allow the tree to maximize its energy storage. Secondly, most insects that carry diseases like Dutch elm disease and oak wilt are not active during the winter. Open wounds on trees during the growing season invite these pests and can cause disease.
Where should a pruning cut be made?
- At the trunk or as close to the trunk as possible.
Just outside the branch collar.
- Anywhere, it doesn’t matter.
- You should never cut out a branch.
Pruning just outside of the branch collar leads to the fastest wound closure. The branch collar is actually trunk tissue, so if we cut into the trunk tissue the tree has a harder time growing over the wound. Each year trees put on one new layer of growth on the outside of the whole plant, it is this growth that actually closes pruning wounds!
True/False – Trees heal from their wounds.
False – Instead of healing like humans where new tissue is formed from the inside to close a wound, trees simply compartmentalize wounds. They do this by covering them from the outside, using the branch collar or callus wood and chemically from the inside by filling cells with decay busting compounds.
Why should you prune a tree?
- To remove dead, diseased and deranged limbs.
- Because the top gets scraggly.
- To create space between my house and the tree.
Although there are several reasons to prune a tree, some of the most common are to create clearance between the tree’s branches and the house. Branches move in the wind and can cause damage to roofing materials as well as windows, gutters and eaves. Dead, dying, diseased and broken limbs can also be removed to clean up the appearance of your tree as well as reduce the possible hazard of a limb falling out of the tree.
How much can/should you remove when pruning?
- At least 10% of the canopy.
Up to 25% on young trees.
- Just one layer of branches from the bottom.
- Everything beyond 30 feet.
Every tree is different, but as a general rule of thumb, you should never remove more than 25% of a tree’s canopy. This is even less for large trees that have begun to slow their growth. If you stick to the three D’s of tree pruning, dead, diseased, deranged (or broken) you are usually safe. Approach pruning these off first, get your building clearance and then begin thinking about raising the canopy so you don’t get smacked in the head next time you mow the lawn.
Can I prune my own trees, when should I hire a pro?
You can prune your own trees, provided you don’t leave the ground, if you need to get over 10 feet hire a pro.
- You should never prune a tree without a pro.
- Pros? They just take your hard earned money.
- Only hire a pro if your branches are greater than 6 inches in diameter.
Although hiring out pruning for a large tree can be expensive, it is worth it when you compare the cost to the possibility of falling out of the tree or off the ladder. We recommend that if you need to get off the ground to reach an intended cut that is the time to hire a pro. If you are really unsure about how to approach pruning, hiring a pro is also a good idea. Just make sure that they are insured, have an ISA Certified arborist on staff and that they are registered to work in your city if your locality has a tree registration program.
How far away from the house should branches be?
- At least 15 feet.
- You shouldn’t even keep a tree close to the house.
Anywhere between 3-8 feet is usually fine.
- It doesn’t matter if the branches touch the house.
When pruning for building clearance, almost any distance is fine. You want to make sure that the branches are not touching the building and causing possible damage, while not making the tree look funny. If you aim for three to eight feet of clearance you generally get that balance. Too little and you will be back to prune next year, too much and you could harm the tree or make it look unbalanced.
What tools do I need to do it right?
- Just a chainsaw.
- A ladder and a chainsaw.
Hand pruning tools such as a hand saw and a hand pruner.
- A lopper works perfect.
A sharp hand saw, preferably with a curved blade and a sharp bypass style hand pruner is typically all you need to prune a tree. You can also get a pole saw or a pole lopper to get some of those pesky branches higher up in the canopy, but stay away from the gas powered pruners – they are hazardous to those that don’t have experience.
True/False – Pruning wounds need to be covered with sealant to close.
False – trees make their own sealant, so adding another compound only slows the closure process down. The closure process is triggered in part by oxygen coming into contact with the newly exposed tissues, so covering them up extends the response. Sealants also trap moisture against the wood, which can speed up the decay process. Remember, trees prune themselves in the woods and close the wounds without any human intervention.
My tree is too big, how do I make it smaller?
- Selective reduction
- Growth regulators
Both selective reduction and the use of growth regulators such as Cambistat® can be helpful in managing the size of your tree.
Although it is usually, difficult if not impossible to significantly reduce the size of your tree, selective limbs can be cut back to make individual limbs shorter and make the tree appear smaller. Adding growth regulators slows the growth of trees and allows the selective reduction pruning to stay for up to three years.
DO NOT top your tree, this is an extremely harmful pruning practice that ultimate creates a hazard out of your tree as new branches sprout. Decay is invited with large pruning cuts that, because of their angle, collect water.