Aquilaria sinensis (Lour.) Gilg, with a common name Heung tree or Incense tree, is an evergreen tree native to south China. Its trunk is smooth and in light grey colour, leaves are oval-shaped with fine veins, and flowers are small and in yellowish green colour. In summer, plenty of oval-shaped green fruits can be seen hanging on it. It is a useful plant as the resin extracted from wood can be used for making incense and Chinese medicine, its wood for joss sticks, and its bark for paper.
What is the relationship between this handsome tree and the name of the place we are living in? Despite various explanations for the origin of the name of Hong Kong, the most popular belief is that Hong Kong derives its name from “Fragrant Harbour” or “Incense Harbour”.
According to Hong Kong and its External Communication before 1842, a book written by Professor LO Hsiang-lin and other reference materials, Heung tree was planted in large numbers in Tung Koon (Dongguan) District and the New Territories of Hong Kong, particularly at Lik Yuen (Shatin) and Sha Lo Wan (the west of Lantau Island) during the Sung Dynasty (619-970 A.D.). The products of Heung tree, pieces of incense each shaped like an amber, were transported through land routes from the production areas to Tsim Sha Tau (now Tsim Sha Tsui) and then by sampan to Shek Pai Wan (now Aberdeen), where incense products were finally exported to destinations in the Chinese mainland, Southeast Asia and places as far as Arabia. Shek Pai Wan, the harbour exporting incense, was therefore named “Fragrant Harbour” (“Heung Harbour”), to the extent that the whole island was later known as Hong Kong.
However, during the early Ching (Qing) Dynasty (1662 –1720 A.D.), in order to counter the coastal attacks by pirates, all coastal habitants were evacuated to inland areas. Therefore, the planting industry of Heung tree was seriously affected.
The species has been categorised as “vulnerable” by the International Union for Conservation of Nature (IUCN) and listed as a Wild Plant under State Protection (Category II) in China owing to the decline in its wild population in south China. As the climate and soil condition in Hong Kong are suitable for the growth of Heung tree, we have some of the best remaining healthy populations of A. sinensis andit is not difficult to find this species in our countryside. While large-scale cultivation of Heung tree for economical uses has disappeared in Hong Kong, the existing populations are currently under threats of illegal felling for harvesting agarwood. Nevertheless, seedlings and young trees are still commonly seen throughout the countryside of Hong Kong.
To conserve this species, the Agriculture, Fisheries and Conservation Department has devised an Incense Tree Species Action Plan (English only) to iron out a series of conservation measures to achieve the long-term viability and sustainability of the local Heung tree populations.
Flowers and leaves of Aquilaria sinensis
Fruits of Aquilaria sinensis