A Mighty Buttress

Buttress of Tetrameles nudiflora

The phenomenon of buttress is a typical feature of arbor trees in the tropical rain forests, and the most mysterious part in the descriptions of the early European adventurers for the rain forest. Some huge trees in the tropical rain forests, generally will grow out some winged structures in the bottom parts of their trunks, the shapes look like board walls; therefore, people often call them buttress. Large-sized butress can be as tall as more than 10 meters and may extend as wide as 10 meters, which will form huge side-wings for the tree trunks; and the scenes are really magnificent. Buttresses are formed because the secondary roots grow outward, and they are also a kind of additional support structure for the trees. Buttresses generally radiate out and usually they have 3-5 pieces. The side of the tree that undertakes burden develop Buttresses the most quickly. In the tropical rain forests of Xishuangbanna, Tetrameles nudiflora R.B is the most representing plant with buttresses; ficus elastica and wiliwil can also grow board-roots. 

In botany, Tetrameles nudiflora R.B is a unique specie of large arbor trees, and Buttress is also a rare phenomenon. Tetrameles nudiflora R.B mainly scatters in tropical areas of Asia, and now they can only be found in East Yunnan of China. It is the most typical and the largest plant with Buttresses in China, and is now being listed as a Class B protection plant of the national level. 

The largest buttress in Xishuangbanna is a Tetrameles nudiflora R.B in Mengla County. It is as tall as 40 meters, and has altogether 13 Buttresses; the tree occupies a land area of 55 m2; of all its Buttresses, the largest is as long as 10 meters, with a height of 3 meters. There is also a huge Tetrameles nudiflora in Xishuangbanna Tropical Botanical Garden, and many visitors go to visit it everyday. The visitors often marvel at the huge living board walls. Some careful visitors may also find that, in the middle of the huge living board wall, there is a big concave; this is because the local farmers cut a piece from the board root and made it into a round wheel for a cart dozens of years ago. 

Why arbor trees of the rain forests can grow Buttresses? It's impossible for common people to comprehend the miracles of nature at the present. Each creature comes to the world and exists at the same time, and each has reasonable rules and ways of survival. However, we may just have a guess about the reason: because the arbors in the tropical rain forests not only grow very tall, they are also very heavy; besides, most of them are plants with shallow roots; but in the same time, they have to brave the storms and winds of the forests. So, in order to stand stable, they grow some buttresses to support themselves. Besides, because they have Buttresses, it will take many people to hold big trees arm in arm, and thus makes it very difficult for people to cut the trees down.