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Is a Cactus a Tree? Everything You Need to Know!

Argentine Giant Cactus_Elena Odareeva_Shutterstock

Simply put, a cactus is not a tree. They are in completely different categories, despite the fact that some cacti are tall and look a lot like a tree. There are many differences between these two plants. For instance, cacti have soft stems, while a tree is made from wood. Trees have bark; cacti do not.

Furthermore, there are also many smaller cacti out there. However, you’d be hard-pressed to find a tiny tree that is the same size as some of the small cacti out there (naturally, at least).

Plus, cacti are considered succulent plants. On the other hand, trees are not. While some trees can live with very little water, most of them cannot live with as little water as a cactus. For these reasons, cacti and trees are not considered the same.

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What is a Cactus?

Euphorbia Cactus
Image Credit: Hans, Pixabay

Since a cactus is not a tree, what exactly is it?

Cacti all belong to the plant family Cactaceae, which contains all the cacti in the world. There are about 127 genera of cacti containing 1,750 different members. That is a lot of different cacti! These cacti come in a range of different sizes and live in many different environments. Most cacti live in areas that are subject to regular droughts. However, not all cacti do.

The Cactaceae family is categorized into the Caryophyllales order, which contains a wide variety of plants. The plants in this order would represent the closest-related plants to cactuses as a whole, and you’d be surprised by some of the plants it contains.

For instance, many carnivorous plants fit into this category. You’ll also find a variety of flowers, including carnations. Seemingly random plants like beets are included too. All of these plants are somewhat related to the cactus—more than a tree is, anyway.

Are Cacti Flowers?

While some cacti do flower, they are not technically categorized as “flowers”. In fact, there is no category specifically for flowers. While there are many plants that people commonly call flowers, most plants do flower—even if they have very small flowers. For instance, tomato plants flower, though humans don’t commonly refer to tomato plants as “flowers”.

Plus, the plants humans do refer to as “flowers” come from a wide range of categories. They’re known for their particularly pretty, fragrant, or large flowers. However, this physical characteristic doesn’t necessarily mean that all these plants are related.

Are Succulents a Tree?

Silver Ball Cactus_Pingky_P_Shutterstock
Image Credit: Pingky_P, Shutterstock

There are many families and genera of succulents. Some of these could be described as “trees.” However, they are not closely related to other trees. Instead, they are more closely related to other succulents. Therefore, just because a succulent may grow into a larger plant resembling a tree, it isn’t actually related to other trees.

With that said, what exactly counts as a tree and what doesn’t is difficult to determine, as there is no set definition. Sometimes, people refer to anything with an elongated stem as a tree, which would include some succulents. However, others categorized trees as things made from wood. Most succulents are not woody in this sense.

Therefore, while some succulents could be defined as trees, it really depends on who you ask. The varying definition makes “trees” difficult to pin down.

What is the Difference Between a Tree and a Cactus?

Baioensis Cactus_Besjunior_Shutterstock
Image Credit: Besjunior, Shutterstock

There are many differences between a tree and a cactus. However, because the definition of a tree is somewhat confusing, these differences may vary depending on who you ask. Usually, trees are defined as having a bark or wood-like substance. Typically, cacti have soft stems that don’t fall into this category.

Furthermore, most cacti are very drought-tolerant, while trees are not. Some trees do need more water than others. However, cacti can usually survive with far less water than a tree. For this reason, cacti grow in very different areas from trees. You may find them growing side-by-side in some areas, but this is rare.

At the same time, cacti can grow to varying heights. Usually, trees are rather tall. Therefore, cacti vary a bit more than trees, though you can also find some very tree-like cacti. You can also find cacti that are extremely small and look nothing like trees.

Often, cacti have needles, while trees do not. At the same time, different cacti have different needles. Some of them are not particularly “needle-like” at all.

Is a Desert Tree a Cactus?

There are many different types of tree-like things that grow in the desert. Some of these are cacti, and some of them are not. For instance, Joshua Trees are not actually trees. Instead, they’re succulents, which puts them in a similar category to cacti.

Other trees may grow in the desert, though, and be actual trees.garden flower divider

Conclusion

A cactus is technically not a tree by most definitions. They are not woody, have no bark, and grow in different areas than trees. Plus, they are not closely related to anything that is often considered a “tree.” Instead, cacti are more closely related to certain flowers and plants like beets.

However, the definition of a tree varies widely. There isn’t a set botanical or common definition for a tree. Therefore, some experts might categorize some cacti as a tree. Again, it all depends on their exact definition.

You might also like: 5 Types of Cholla Cactus (with Pictures)


Featured Image Credit: Elena Odareeva, Shutterstock

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