Why are some trees hollow?

We often see some old trees, although the trunk is hollow, but the leaves are still green. So how do trees survive when their trunks are empty?

If you cut through the trunk to look at the section, it is common to see that the structure of the stem is as follows: the outer layer is the epidermis, on the epidermis is often hairy or thorny; inside the epidermis is the crust, in the crust there are some thin-walled organizations and relatively solid organization, that is the middle pillar of the body.

In the middle cylinder there are capillaries , which are the most important part of the plant body, they have the function of conducting water and nutrients. The middle of the middle pillar is also the most central part of the trunk, called the medulla . The medulla has very large thin-walled cells, which store nutrients.

Bamboo and bamboo are among the hollow plants.

But there are some plants like wheat, water rice, bamboo, reeds, vegetables . the trunk is empty. This is because the marrow of the plant stem has long been degraded.

In fact, that plant also has a dense body, but the hollow body is more beneficial to the plant , so in the long-term evolution, the body became hollow.

Why are hollow stems beneficial to plants?

The mechanical and capillary bodies found in the plant body are like beams in reinforced concrete architecture, because they support the tree and will not fall.

We know that with the same amount of material, if a pillar is relatively large and hollow, the resistance is stronger than a small, dense column. If the plant body has more mechanical and capillary organizations, reducing, even losing the soft marrow, forming a tubular structure, the body's support is both large and material-saving.

The plants belonging to the rice stem family such as wheat, water rice, reeds, bamboo, bamboo, are the most evolved plants so most of them are hollow.

There are some agricultural crops (wheat, wet rice) that are also prone to fall, because the mechanical organization in their body is not very developed. We can use methods to limit the amount of water and nitrogen fertilizer, increase potassium fertilizer, to strengthen the mechanical organization of the trunk.

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