Which tree species can produce agarwood?

Only four specific families and genera of Oleaceae, Lauraceae, Daphne and Euphorbiaceae can produce agarwood.

To produce agarwood, these four families must meet the following conditions:

There are mature and developed resin glands on the trunk (usually trees over 30 years old).

Second, there is a wound on the tree, which may be caused by knives and axes, natural forces or insects and ants. The wound cannot heal in a short time and remains for a long time. ?

Injury is a necessary condition for incense. Once the agarwood tree is injured by external force, it will immediately produce a stress reaction as a life experience and secrete a lot of juice. It mainly includes three components:

One is nutritional factor, which is compared to "red blood cells" of trees. Its function is to provide nutrients and promote the recovery of injured tissues.

The second is antibody factor, which is compared to "white blood cells" of trees. Its function is to resist foreign invasion and infection.

The third is the coagulation factor, which is compared to the "platelet" of the tree, so that the wound is partially coagulated to ensure that the sap of the tree will not be lost in large quantities.

Third, in addition to trunk injury, it needs to be infected by mold, and the tissues around the wound begin to fester due to infection, so the sap in the sap ditch is stimulated by this, alienated into a creamy lump, blocking the surrounding tissues, and the festering continues to deteriorate and spread.

Under various conditions, in the agarwood tree, fungi continue to expand infection, constantly interact with various factors in the tree, constantly produce aromatic substances, and are constantly condensed in blood vessels by the coagulation factors of the tree. This process of infection, reaction, aromatic substance production, coagulation and re-diffusion infection continues. This cycle is called persistent infection stage.

This stage is the guarantee that the fragrance will eventually produce an agarwood.

Extended data:

Identification of agarwood

Domestic agarwood: irregular blocks of different sizes, with dead wood removed, longitudinal grooves and different lengths of longitudinal edges. The xylem with sufficient oil is dark brown and slightly shiny, the xylem with little oil is light brown, and the xylem with little oil is yellow and white, and the light and dark colors are interlaced to form longitudinal patterns or flower stripes.

Insect wounds and wounds are yellowish brown, rough and withered. Scraggy may have holes, often accompanied by traces of soil. Oil is hard and heavy, and it will sink or semi-sink when entering the water; Those with little or no oil will float when they enter the water. Easy to ignite, smoke is emitted when burning, black oily resin emerges, and it has a strong aroma. The smell is fragrant and slightly bitter.

Imported agarwood: striped or helmet-shaped, with yellowish brown to dark brown surface, inconspicuous pattern, slightly shiny, and dark brown resin condensed on the surface. Hard and heavy, not easy to break, and the wood fiber on the longitudinal crack surface is thicker. The smell is the same as that of domestic agarwood, but it is stronger.

The above two kinds of agarwood are black in color, heavy in resin and better in water.

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