Consolidating the experience from the past and present as well as information found in Chinese herbal articles, five factors for agarwood formation have been identified, namely “raw formation”, “ripe formation”, “removal”, “insect attack” and “fungal infection”.
When wounds are developed or branches are broken due to destruction by natural forces such as windstorms and thunder, animal scratches or logging by men, trees will produce resin to heal its wounds, during which agarwood will be produced. The longer the process, the better the quality of the scented wood.
Trees may wither and die of continual production of resin which leads to blockage of its canals. Over a long period of time, the wood fibres will blend with the resin and solidify into superior hard and dark agarwood which sinks in water. Meanwhile, the life of the agarwood tree is brought to an end.
When the wounded parts of trees come off as a result of infection in large and small pieces, they may contain remnants of resin, which will blend with the wood textures, forming agarwood.
Trees that are bitten and attacked by parasitic insects will produce resin for self-protection and healing, and agarwood will be formed as a result.
At the initial stage of fungal infection, the amount of resin formed is very small. However, prolonged infection will engender high quality agarwood.