Banyan is an evergreen broad-leaved tree with high temperature and rainy weather and high air humidity. Distributed in tropical and subtropical areas of China, it is common in low-altitude tropical forests such as Yongzhou and coastal low-humidity areas. Because the fruit of banyan is sweet, birds like to eat it, and hard and indigestible seeds spread everywhere with bird droppings. Small banyan trees sown by birds can be seen on ancient towers, ancient city walls and ancient roofs in tropical and subtropical areas. Small banyan trees that grow on trees in tropical forests are mostly sown by birds. This strange phenomenon of trees on trees constitutes a major landscape of tropical forests.

Banyan has a long life, fast growth and well-developed lateral branches and roots. There are many lenticels on its trunk and branches, and many aerial roots can grow everywhere and hang down like handfuls of beards. These aerial roots grow downward and thicken into column roots, which are unbranched and leafless. The aerial rooting function of banyan, like other roots, has the functions of absorbing water and nourishing food, and at the same time, it also supports the outward expanding branches, so that the crown of the tree continues to expand. According to statistics, a huge old banyan tree has more than 1000 supporting roots. A big banyan tree growing in urban and rural areas around Xinhui County, Guangdong Province, has a crown of more than 6,000 square meters, and there are thousands of column roots under the crown, like a dense "forest". Because this "forest" is not far from the sea, it has become the habitat of birds such as cranes and storks that eat fish at sunrise and stay overnight, forming a famous "bird paradise".

Inspired by the growth characteristics of banyan trees, gardeners ingeniously induced and reshaped the aerial roots and crown of banyan trees, making it a unique landscape in courtyard greening and a bonsai with Lingnan characteristics.

In addition to banyan trees, other trees can also grow supporting roots, such as Ilya palm of Palmae, Pandou tree of Rumex family, Congo mulberry of Moraceae, Casuarina Sumatra of Casuarina family, Delun peach of Delun peach family, etc.