How to get rid of Leylandii trees?

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A Leylandii or Cupressus Leylandii is part of the evergreen coniferous family. It is known for its fast growth, and large size and is commonly used for landscaping purposes. One of the many uses of this tree is for privacy as it can grow to about 50 feet even with poor soil quality.

Let’s take a look at some of the ways of removing your Leylandii trees as well as killing their root system along the way.

Before we proceed, I would like to note that killing a tree or removing it is not always an easy project to tackle. If you would like to get the job done by a local company, feel free to submit this form to get a quote.

How to kill Leylandii trees?

When you are looking for methods of killing Cupressus Leylandii, you have to go for something easy and efficient. You can choose from a variety of options:

  • Foliar Spray
  • Cutting the tree down and treating the stump with Herbicides
  • Gridling or ring barking
  • Basal Bark treatment
  • Injecting the tree with killing chemicals
  • Cut surface treatment

To understand learn more about these methods to kill a tree without cutting it, make sure to check this article out.

It should be noted that even though any of the above methods can be used to kill a Cupressus Leylandii, it will still have to be taken down and dealt with once the tree dies. Even more so if the Leylandii is located in your backyard.  

The best way to kill a small Leylandii tree

When a Cupressus Leylandii is in its initial years of growth, it can be from a few feet tall to 20 feet high. If the tree is still less than 10 feet, the foliar spray would be a great way to approach the challenge.  

Steps to Kill a small Leylandii:

  1. Make sure there is no wind during this as the herbicide can get carried away.
  2. Use an effective herbicide like Roundup, Ortho or Triclopyr. (Here’s my recommended producs page)
  3. Spray the foliage of the Leylandii with the herbicide.
  4. The herbicide will be absorbed by the foliage and transported to the roots killing the tree slowly.  

One of the other reasons why this method is preferred is because Cupressus Leylandiis are usually used as hedges. Thus this variety is usually grouped together as a hedge. Foliar spray is really effective in killing grouped small trees. Spraying herbicide on a hedge you can do in one go, without needing excessive repetition.

Summer and late spring would be the best seasons to apply the method since the tree’s nutrients are the most active.

The best way to kill a big Leylandii tree

A large Cupressus Leylandii can grow up to 70 feet tall. The species is also known for its thick and large foliage, therefore you will have to select a technique that is especially effective.

Ringbarking would be the most efficient method for killing a large Leylandii or Cupressus Leylandii as bark removal will stop the nutrient flow within the tree.

Steps to kill Leylandii by ringbarking:

  1. Get a hatchet, axe, chainsaw or a handsaw for this method.
  2. As the name suggests, remove a ring of bark around the entire tree’s diameter, about 4-8 inches wide. You can even create two of those rings, few inches apart from each other.
  3. Spray the exposed bark with herbicide to maximize the chances and speed up the process.  

Killing a small Leylandii compared to a big Leylandii – What are the differences?

Although most methods of killing trees can be used regardless of the size of the tree, some of them are just going to be inefficient.

For example,  Foliar Spray is a great method for killing small Cupressus Leylandiis because of their large foliage, but this method will end up taking a lot more time if the same tree grows more than 10-15 feet tall. The herbicides will take a lot more time traveling to the root system.

The other major difference is the time it takes for the tree to die no matter which method you use. If you use ringbarking for both small and big, the smaller Cupressus Leylandii will die much faster.

Another difference is that when a tree is young, it has not established its root system properly so any killing technique will be more efficient when compared to a matured tree.

A young tree requires much more nutrients to grow, therefore a technique like ringbarking which stops nutrient flow to the leaves will have a greater impact on a small tree.

Can you kill a Cupressus Leylandii without cutting it down?

Leylandii or Cupressus Leylandii can be killed without cutting them down. The preferred methods for doing so would be ringbarking, basal bark treatment, or cut surface treatment.

Consider the fact that once the tree is dead, it will start decomposing over time and the tree can fall on nearby property, especially during windy weather.

Things to consider before removing a tree on your own

Killing a tree can be quite straightforward, especially when you know how to follow the procedures related to the technique.

But you have to take into account, that even once a tree is dead, you have to take it down. Otherwise, the tree will start decomposing and it can fall down unexpectedly. This is dangerous if the tree is not located in a remote area.  

Recommended reading: How to tell if a tree is dead

Hire a professional tree removal service

As I have mentioned before, a Cupressus Leylandii can grow big, hiring a professional will solve most of your logistical problems once the tree is dead. This involves, cutting it down, transporting it, and preparing the wood for whatever use you want out of it.

I will be publishing a tree removal cost guide in the near future so you would know how much it costs to hire a professional tree removal service.

Or you can submit this form to get a free quote.

Frequently Asked Questions

Can you kill a Cupressus Leylandii with salt?

You absolutely can. Pouring salt water near the roots regularly will slowly kill the tree. This is a good method if you don’t want to use any chemicals in your garden. Be aware that it will also kill any nearby vegetation.

What is the best time to kill a Cupressus Leylandii tree?

If you are using the Foliar Spray method, you should ideally kill the tree during spring or summer. On the other hand, if you are using girdling then start the process during autumn or winter.

How deep are Leylandii tree roots?

Cupressus Leylandii can grow big but their root systems are shallow and wide. This of course also depends on the age of the tree. For a young Leylandii, the roots will not be as widespread.  

Can I use Leyland Cypress as firewood after killing it?

Once the tree is dead, it is already seasoned, so theoretically you can use Cypress Leyland as firewood right after cutting it down, assuming it has already dried out beforehand. However, Leyland does not make good firewood because of its high sap content and low density.


Out of all the methods available to kill trees, the ringbarking and foliar spray would be the most efficient way to kill Leylandii and its root system

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