Samanea saman

The *Samanea saman* is a massive, semi-deciduous flowering tree. It belongs to the Fabaceae family, which is the pea family. It is also part of the Mimosoid clade. This species is native to Central and South America. However, it has spread widely across the tropics. You can find it in South and Southeast Asia and the Pacific Islands.

It is a very famous tree in many different cultures. In English, it is often called the rain tree, saman, or monkeypod. In Cambodia, it is known as the Chankiri Tree.

The tree is famous for its unique growth pattern and shape. It develops a very wide, symmetrical, umbrella-shaped crown. This large canopy provides massive amounts of shade. The leaves are pinnate, meaning they consist of 6 to 16 small leaflets. Each leaflet is shaped like a diamond. These leaflets have a dull top surface and are finely hairy underneath. The leaves also show a specific movement. They fold up during the evening or when it rains. Because of this, people call it the "five o'clock tree."

There are many different parts to the tree's life cycle. The flowers are pinkish with white and red stamens. These flowers grow in clusters called heads. Each head contains between 12 and 25 individual flowers. A single tree may have thousands of these flower heads. After flowering, the tree produces curved, leathery seed pods. These pods contain flat, oval seeds covered in a sticky, edible flesh. The tree is also semi-deciduous. This means it sheds its leaves during dry periods to survive.

History shows how much people have noticed this species. The explorer Alexander von Humboldt studied these trees in the Americas. He traveled through the region from 1799 to 1804. In Venezuela, he found a giant specimen near Maracay. He measured its umbrella-shaped crown at 576 feet wide. The trunk was about 9 feet in diameter. Local tradition suggests this specific tree might be over 500 years old. It is now considered a Venezuelan national treasure.

The tree has significant biological and environmental value. In Indonesia, mature trees help with carbon sequestration. Carbon sequestration is the process of capturing and removing carbon dioxide from the atmosphere. Research shows a mature tree with a large crown can absorb significant amounts of CO2 every year. This helps manage the gases in our air. The tree also supports other life forms. For example, it is a host plant for lac insects. These insects create a hard material that humans collect to make shellac. Shellac is used for wood finishes and lacquerware.

Humans use many parts of the *Samanea saman* for different purposes. The wood has high chatoyance, which is a shimmering quality. This makes the wood excellent for carving and making furniture. The fruit pulp is also useful. It has a taste similar to lemons and can be made into a beverage. In some cases, the pulp is even used as an additive to gasoline. In Cambodia, people may eat the fruit, and during famine, they have eaten young leaves in salads.

Despite its beauty, the tree can sometimes be dangerous. Its large branches tend to break off during heavy rainstorms. This is a concern because the tree is often used for avenue plantations. This means it is planted along roadsides. In Cambodia, the Chankiri tree has a somber history. Some trees were located at the Killing Fields. During the Cambodian genocide, these trees were used by the Khmer Rouge. It is important to note that there is no local association between the tree species and the regime itself.