7 Reasons Why Topping Trees Is a Bad Idea (+Alternatives)
The method of topping trees isn’t a recommended pruning practice in arboriculture. In fact, it’s possibly the worst thing you could do to the health of your tree.
Topping is when you cut back the main vertical leaders of the tree.
When a tree is topped, it’s usually done to control the height and spread of a tree. This might be a quick fix in the short term, but it has detrimental long-term effects on the overall health of the tree.
It can lead to branch dieback, decay and unstable tree structure, resulting in potentially hazardous situations for property owners and urban landscapes.
Keep reading to learn more about the main reasons why not to top a tree and what pruning practices to choose instead.
1.Undernourishment
Good pruning methods rarely remove more than 25% of the live tree branches so not to interfere with a tree’s ability to produce nutrients and recover adequetly.
Tree topping seriously disrupts the tree’s already established crown-to-root ratio and temporarily cuts off its food source and nutrient-producing ability.
2.Shock
A tree’s crown is like an umbrella that protects much of a tree from direct sun rays. By topping a tree, you remove this protection and overexpose the bark to the elements.
It also affects the neighboring trees and shrubs. Especially if these neighboring trees thrive in the shade, it can lead to poor health or even death after the shade has been removed.
3.Insects and Disease
The large cuts after the tree has been topped have a difficult time healing. Large wounds and branch stubs left by topping are vulnerable to insect invasion and fungi.
If a tree wound doesn’t heal adequately (compartmentalize the wound), then it’s only a matter of time before the decay and disease spread further.
4.Weak Structure
The new growth after the tree has been topped (often called water sprouts) is more weakly attached. As a result, topping trees ruins good tree structure and makes them more susceptible to breaking and failing.
The new limbs grow more rapidly and in larger quantities than normal new growth which leads to far denser crown.
If the crown is too dense, there isn’t enough air and light penetration in the canopy.
5.Potential Tree Death
Some trees are more tolerant of topping than others. However, many trees suffer a severe shock after being topped and don’t recover.
6.Unattractive Shape
A topped tree develops multiple tops, which look asymmetrical. Even with its regrowth, it never regains the same natural strength and grace.
You’ll often find topped trees under the utility lines or power lines.
7.Cost
A topped tree requires ongoing maintenance at best, if not the replacement of the tree after it dies or the cost of property damage if it falls because of weakened structure.
What to Do Instead of Tree Topping?
Instead of topping, consider more sustainable and healthy tree pruning practices to retain the tree’s natural shape. Pruning techniques like crown thinning, crown reduction, or canopy raising can help manage a tree’s size and shape without causing the harmful effects associated with topping.
Consulting with a qualified arborist is the best way to ensure that your tree is pruned correctly. They can provide expert advice on the best course of action to enhance tree health and safety while maintaining its natural form and beauty in the long run.
FAQ
What Happens if You Keep Topping a Tree?
Each topping cycle increases the tree’s vulnerability to pests and disease, weakens its structure, and can eventually lead to its death. Continuous topping results in a tree that is not only unsightly but also poses significant safety risks due to the development of weaker limbs and overall instability. However, it’s important to distinguish between topping and pollarding. (see below)
What is the Difference between Topping Tree and Pollarding?
Topping involves cutting back branches and stems to reduce the size of the tree regardless of their age and diameter, often leading to cracks and decay within the tree. In contrast, pollarding involves cutting branches at the same pruning cut on growth that is less than two years old, which helps minimize decay.
Pollarding is a high-maintenance pruning practice that requires annual or biannual pruning, but it can result in unique trees with long lifespans. Due to the regular pruning requirements, this practice is becoming less common, with people increasingly opting to plant small-sized trees instead.
| Aspect | Topping | Pollarding |
|---|---|---|
| Commonality | Commonly practiced, yet inappropriate technique | Rarely practiced, yet appropriate technique |
| Cutting Technique | Make heading cuts through regardless of diameter or age | Make heading cuts through one to a few years old, no more than about 1 inch in diameter |
| Age of Trees | Practiced on trees regardless of age | Training begins when tree is young |
| Pruning Frequency | Tree may or may not be pruned again | All shoots removed every one to three years back to the same position on the tree, never below the original cut |
| Tree Types | Practiced on many types of trees | Appropriate species include sycamore, lindens, horse chestnuts, and others |
| Impact on Tree Health | Initiates decay in cut branches and trunk | Does not initiate trunk decay |
| Structural Integrity | Leads to weak structure and could place landscape at risk | Maintains good structure |
| Lifespan | Can lead to short life | Pollarded trees can live for centuries |
Do Trees Grow Back After Being Topped?
While trees do try to grow back after being topped, the regrowth is typically problematic. The new shoots, known as water sprouts, grow quickly and are weakly attached to the tree.
This vigorous regrowth is often more prone to breaking, leading to an increased risk of damage during storms or high winds. Although the tree attempts to survive, it is never able to fully recover its original form or strength, resulting in a weakened, unattractive, and potentially dangerous tree.
What to Do with a Tree that Has Been Topped?
Unfortunately, the damage was already done after the tree had been topped. It can’t be fully reversed. The only thing you can do is ongoing monitoring, maintenance and pruning.
In some cases, it might be necessary to consider tree removal.
If a tree needs regular pruning to keep it small, the wrong tree was planted on that site in the first place. Consider cutting it down and replanting it with an appropriately sized tree.
