Agarwood comes from the "wound healing" of trees in the Aquilaria genus of the Thymelaeaceae family. Different ways of injury produce agarwood with different characters.
The agarwood tree itself is not fragrant; the fragrance comes from its self-repair after injury. When the trunk is naturally broken, gnawed by insects or ants, or wounded by human harvesting, the tree secretes resin-like substances to seal the wound, and only after years of aging does it condense into what we call "agarwood." So within the same producing region, different formation methods lead to great differences in scent and appearance.
Living-tree formation is agarwood formed from injury while the tree is still alive, and its scent is usually clearer and more lively in layers; mature formation is when the tree falls or dies, and the fragrant body continues to age in soil or water, giving a fuller, more restrained aroma. Neither is superior; they simply have different characters—it depends on which expression you personally prefer.
Insect-hole formation is agarwood induced by termites, longhorn beetles, and other insects or ants gnawing the tree body; the scent lines often follow the insect tunnels, creating unusual and interesting shapes. Fallen formation is when branches naturally die and the fragrant body falls from the tree and continues to form. This type of agarwood often looks beautiful in its natural shape, and many incense enthusiasts use it as a hand piece or display object.
The formation method determines the underlying character of a piece of agarwood, but whether it smells good is ultimately decided by the nose.
Understanding formation types is not about memorizing terms, but about giving you one more angle when looking at a piece of material: was it formed on a living tree or aged after the tree fell? Do the insect tunnels run naturally? Looking at these together with scent and resin makes your judgment more reliable. When you visit the shop, you can also ask the owner about the origin of the material.
Explain your specific situation clearly, and we will give corresponding judgments and suggestions—sourcing, personal use, and appraisal are all accepted.
Ask about agarwood-related questions