In this article, I’ll be discussing all you need to know bout tree crowning.
For those who don’t know, the tree crown is the upper part of a tree, consisting of branches that grow out from the main trunk. These branches support the leaves which are vital for photosynthesis.
What Does Tree Crowning Mean?
All trees have crowns, however, different tree species have different crown shapes and sizes. Hence, tree crowns take their form specific to the function they play in nature, that is if their crowns are not altered by pruning.
There are different variations of tree crowns, and I will discuss each below.
Dominant Tree Crown
A dominant tree crown is one that grows over all the other surrounding plants. This includes the crown of other trees.
The dominant crown makes it possible for the tree to absorb more direct sunlight than all other tree crowns. It achieves this by pushing its branches both upward and outwards. Doing this will guarantee that its leaves receive as much sunlight as possible.
A strong central trunk is the main feature of a tree with a dominant crown. The crown is also usually shaped like a pyramid that has branches growing outwardly.
Trees are known for having dominant tree crowns include the Red Oak, found in the U.S hardiness zones 4 to 9. The Mountain White Gum is also a great example. It lives in the U.S hardiness zone 8 to 10.
Co-Dominant Tree Crown
A co-dominant tree crown does not monopolize sunlight, meaning it shares other surrounding trees.
As you would guess, the co-dominant crown is smaller than the dominant crown, and it gets its sunlight exclusively from the tips its higher branches.
A co-dominant crown does not allow the tree to grow to its maximum potential, as they share their resources.
Trees with co-dominant crown traits are the same as this that is dominant, the difference being that circumstances of nature force them to share their resources with other trees in their immediate surroundings.
Intermediate Tree Crown
Third, on our list is trees with intermediate tree crowns. This type of crown grows just as tall as the lower ceiling of the forest canopy. This area is right under the co-dominant tree crowns.
Intermediate tree crowns are shorter, and you can find leaves with a smaller surface area on them.
The tree takes advantage of tiny holes in the canopy, thanks to the thinned out leaf placements. This means the greenness of the tree is only possible in areas where sunlight can reach.
The Japanese Stewartia is a great example of a tree with an intermediate canopy. It lives in the U.S hardiness zone 5 to 8.
Overtopped Tree Crown
When they do not receive direct sunlight around wooded areas, trees that are overtopped will grow smaller crowns. They usually thrive best in areas that receive indirect sunlight.
Short stature and sparse leaf presence is a major feature of overtopped tree crowns. Many species of these trees can survive and grow tall when in full sun, but they are they thrive better when in full shade.
In full shade, these trees will grow a lot slower.
A perfect example of a tree with an overtopped tree crown is the Canadian Hemlock. It grows in the U.S hardiness zones 4 to 8.
Types Of Tree Crowns
There are several types of tree crowns, these include –
- Pyramidal crown
- Full crowned
- Vase crown
- Spreading crown
- Layered crown
- Columnar crown
- Weeping crown
How To Crown Lift A Tree
There are situations where a tree grows so large that the crown spreads over your home. In such a case you may be thinking of felling the tree, but there is something else you can do instead – Crown lifting!
Crown Lifting is a tree trimming technique used by arborists and professional gardeners to raise a tree’s crown.
When you understand what crown lifting is, you would find that it is a more preferable option than removing the tree, especially if it’s a healthy tree.
What Is A Crown Lift?
A crown lift is a tree trimming practice whereby the lower branches of a mature tree are removed. Doing this will lift the crown of the tree and create Ade space beneath.
It’s a simple technique for those who understand it.
Pruning your tree crown can be beneficial to your tree’s health. It would also be of an advantage to smaller trees in the surrounding, as they will have access to more air and sunlight.
Crown lift pruning also boosts a tree’s vigor, since resources are better distributed, older trees that have become unproductive can become healthier.
So, if you know anyone who wants to make a hasty decision and cut down their tree because it is overgrown, suggest crown lifting to that person. They will thank you later.
It is one of the easiest surgeries you can carry out on a tree and you only require basic tree pruning tools to execute the task.
Since cutting the lower obstructing branches is the main goal, you may not even need a ladder to perform crown lifting.
Pruning a tree to let in more light and air
For most homeowners, performing a crown lift is the best way to eliminate the problem of shadows cast by the tree across the windows of the house.
A simple crown lift will help your yard access more sunlight. The smaller trees in your yard will be happy about this too, as they would also enjoy more of the sun’s rays, as well as air.
Removing the lower branches will also give your tree a better, neater appearance, so you might want to consider it.
Before you perform a crown lift, you have to consider the time of the year you’re in. For most trees, the winter season is the best time for performing any type of pruning, not just crown lifting.
During the winter, trees are in their dormant state so the pruning wounds won’t be harmful. Also, it is easier to assess the tree branches during the winter, as many of its leaves have fallen off and you will have a clearer view of what needs to be cut.
Winter is also a good time to crown-lift evergreens, as their sap doesn’t flow freely during this period.
Some trees are best pruned in the summer though. The Birch tree is one such tree. They are prone to “Silverleaf”, which is a disease most common in the winter.
How To Perform Tree Crowning
Before you perform a crown lift, you have to make sure the cutting tools you will be using are sharp and clean. If your saw hasn’t been used for a long time, then sharpen it first.
When your blades are sharp, you can achieve clean cuts. Trees heal faster from smooth cuts than they do from rough, jagged cuts.
Also, sterilize the blades with an alcohol-based solution to prevent the spread of diseases.
Follow these steps to perform tree crowning –
Step 1 – Assess the tree
The first thing you need to do before you start cutting is to assess the tree and figure out which branches need to be removed. Remember, you are trying to lift the crown, so the lower branches should be your target.
Stand a few feet away from the tree and do a scan of the lower hanging branches. Also, determine the shape you want the crown to take so you can prune accordingly.
Step 2 – Remove the bottom branches
Begin the crown lift surgery by cutting off the lower branches.
A good tip here is to cut the underside of the branch first. Cut one third through the branch, then cut the rest off from the top. This will stop the branch from falling loosely under its weight.
Step 3 – Reduce larger branches before cutting them off the trunk
If you’re cutting a large branch, then reduce them first before cutting them off. Larger branches are heavy and you wouldn’t want it collapsing to the ground.
Start by trimming the branch from the tip, to fractions across the middle, then to the point closest to the tree trunk.
Doing this will reduce the risk of the branch tearing off the tree.
Step 4 – Assess the tree again
After the necessary lower branches have been cut to the height where you want the crown to start, you can take another step back from the tree to see how it looks.
If it hasn’t yet taken the shape you want, then identify the branches responsibly and prune them off.
Do this a few more times until the crown lift is complete.
Step 5 – Dispose of the branches
The branches you have cut off cannot be left there to rot, rather you should cut them up into smaller pieces and dispose of them.
You can also grind them into mulch and scatter around your garden floor.
Tree crowning is the best solution to a healthy, overgrown tree canopy. It allows better penetration of air and sunlight, which is beneficial to the other smaller plants.
Thanks for reading!
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