7 Possible Reasons Why Do Cypress Trees Have Knees

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If you’re confused about conical-shaped structures formed by the roots of cypress trees, it’s a knee. Not only is it mysterious, but scientists are also confused about what it is for. If you are also wondering why Cypress trees have knees, You Are Not alone.

In this article, I will help you understand Cypress tree knees and why Cypress trees have knees. Even though there is no scientific evidence/explanation of this reason or phenomenon, I will list why scientists have frequently debated and often perceive it.

Different scientists have different beliefs on “Why Do Cypress Trees Have Knees”, which we will discuss in this article. Therefore give this article a thorough look because I am going to shed some light on this fascinating structure and give you a better understanding of Cypress tree’s knees development structure and ecosystem.

What Are Cypress Trees Knees?

Cypress Trees Have Knees

Cypress tree knees are conical-shaped structures usually formed by the roots of cypress trees. Interestingly, it can grow several feet tall and have a rough texture. Surprisingly, scientists are still trying to find the exact purpose of cypress tree knees.

The actual purpose & cause is still to be fully understood, but many believe that it acts as an anchor for the tree and provides better stability in water-logged soils because of its height.

During the research, I learned that cypress tree knees had been a topic of interest for scientists and nature lovers like me for a long time. Despite years of study and research, I’m surprised that we still don’t know everything about these mysterious structures.

However, I hope one day we will have all the knowledge regarding the actual purpose of Cypress trees’ knees because scientists will never stop exploring what they are, why they form, and what to do about them.

However, continue reading if you are still curious about their exact purpose and what you can do if you have cypress trees with knees on your property. Below I am giving you seven possible reasons why Cypress trees have knees.

7 Possible Reasons Why Cypress Trees Have Knees

The information I am giving you below is based on my research and many scientists’ beliefs. There is no evidence that any of the statements below are 100% accurate.

However, most of the reasons are believed by scientists and frequently debated in our community. Below I am mentioning all seven reasons I find relevant and possible for developing Cypress tree knees.

  1. To help the trees access the oxygen, they need to survive. 
  2. To help anchor the trees in place and provide stability.
  3. To help keep their roots anchored and prevent the trees from falling over.
  4. To help transport water from the soil to the roots.
  5. To attract a variety of microbes that are beneficial for the trees.
  6. To help circulate air & keep the roots dry. 
  7. To help transport nutrients from the soil to the roots. 

Absorbing oxygen

During my research, I found that Cypress tree knees may help it absorb oxygen from the water effectively. There is no hard-core proof, but it is still one of the theories that many in our community believe.

Since cypress trees often grow in wetland areas with their roots submerged in water for an extended time, I also think the knees could help them absorb excessive oxygen better from the water.

Structural Support

Maybe cypress trees have knees to provide structural support to the trees. We all know that cypress trees are known to grow tall & slender, which makes them vulnerable to tipping over in high winds or heavy rain. Therefore, it might help anchor the trees in place and provide stability.

Anchoring The Roots

Another similar theory that is quite similar to the previous one is the Cypress tree knees help anchor its roots in place in extreme weather conditions. Cypress trees that are native to wetland areas tend to grow on soil that can be loose and shifting.

Therefore it might be possible that your Cypress trees have knees to help keep their roots anchored and prevent the trees from falling over. This is more common if you get a particular specimen of cypress native to such wetland areas.

Prevent Root Rot

Many scientists believe that the cypress trees have knees to prevent root rot. Root rot is a common problem for trees growing in wet soil. Since the excess moisture can lead to the growth of harmful fungi & bacteria, the knees are there to help circulate air and keep the roots dry, which can help prevent rot.

Improving Water Uptake

According to some scientist theory, the Cypress trees have knees to improve their water uptake. This may also seem more valid and relevant because the cypress tree knees are often found near the roots. 

Helping With Nutrient Uptake

Throughout my research, I also found a few scientists be that few scientists believe it helps in nutrient uptake. I think this is less likely to be the reason, but many people believe Cypress tree knees benefit from transporting nutrients from the soil to the roots, which usually allows them to grow and thrive better.

Supporting Microbial Life

Interestingly, few scientists also believe that cypress trees with knees might be there to help & support microbial life in the soil. This reason cannot go unnoticed because many cypress trees’ knees are thought to create a unique microhabitat in the ground.

Who knows, the cypress tree develops knees to attract a variety of microbes that are beneficial for the trees. You should know that there are still many unknown things about cypress tree knees because more research is needed to understand their purpose and role in the ecosystem fully.

However, I tried my best to come up with the most relevant seven theories that can help you with a starting point to understand the purpose of the Cypress tree knees. 

Do All Cypress Trees Have Knees?

Do All Cypress Trees Have Knees?

No, not all cypress trees have knees. However, you will likely see knees on certain cypress trees, like the bald cypress and pond cypress trees. These two cypress species are most likely to have protrusions commonly referred to as cypress tree knees.

If you visit a swamp or wetland area and come across a cypress tree, there’s a good chance you’ll also see some cypress tree knees. However, as I said earlier, not all cypress trees will have kees on.

Overall, the knees of cypress trees make them unique and different from different trees. However, do note that Cypress tree knees are just one of the many mysterious and fascinating things about them.

How Far Do Cypress Knees Grow From The Tree? 

Cypress trees’ knees form near the roots of cypress trees and don’t always stay close to the tree trunk. You’ll notice these knees growing several feet away from the tree while still being part of the same root system.

Don’t be confused, as this happened because of the extensive cypress tree’s root system, which can extend far beyond the visible portion of the tree. Thus, it can be tough to say how far your Cypress tree knees may grow because the exact distance that knees grow from its tree depends upon numerous factors like the size & age of the tree and environmental conditions. 

Do note that if you have more giant, older trees, they are likely to have a more extensive root system. So, you might also notice its knees growing further away from the tree.

However, as I said to you earlier, there are a few environmental factors, like soil quality, water levels, and the presence of other trees, that can also affect the growth and development of the root system along the distance between your tree and its knees.

How To Get Rid Of Cypress Tree Knees?

If your cypress tree knees interfere with your landscaping or building plans, you might consider removing them. Believe it or not but it can be a tricky process. Therefore I highly recommend you consult an arborist or get professional help.

Depending upon the size & location of your trees’ knees, the professional might have to take or even cut down the tree. Even though it can grow several feet tall, it gives a unique but exciting feature to a Cypress tree.

I don’t find it annoying, well. I have seen many people choosing to live with their knees and viewing them as a quirky feature of their landscape. After all, they’re part of your tree’s root system; removing them can be challenging for your and the tree. It can also stress them out, making their appearance dull and saggy.


What Causes Cypress Tree Knees To Form?

There is no scientific evidence or explanation for the cause of Cypress tree knee formation. However, there are many theories that experts believe, like trees trying to absorb oxygen from the water or the knee are there to provide structural support to the tree. No matter what you think, more research is needed foto better understanding formation.

How Does The Presence Of Cypress Tree Knees Affect Tree Growth?

Through my research, I haven’t found any significant damage or adverse effect of Cypress tree knees on tree growth. Surprisingly, many believe that knees are there to help them grow better. However, more research is needed to determine if there are any long-term effects.

Can Cypress Tree Knees Be A Sign Of A Sick Or Stressed Tree?

No, Cypress tree knees are not a sign of sickness or stress in trees. However, if you notice your Cypress tree is not growing correctly or not thriving as it should be, I recommend you consult a professional arborist.


This article taught you that cypress tree knees are a fascinating and mysterious feature of the natural world. You will likely notice it forming near the roots of cypress trees, looking like knuckles or knots.

As I told you in this article, there are various theories about why Cypress trees have knees, including helping the tree absorb oxygen and providing structural support. Since not all Cyprus read developed knees, you will likely find Cypress tree knees on bald cypress and pond cypress trees.

I tried my best to give you all the information regarding ‘why do Cypress trees have knees.’ If you find this article helpful, then consider sharing it. Your share will help many people learn about the possible causes on why Cypress trees have knees formation. Do check our other articles on tree care and arboriculture. See you in the next post, till then, take care and goodbye.