Oud, explained without the mystique
Oud is resin. When a Aquilaria tree is wounded and infected by a particular mould, it floods the injury with a dark, fragrant resin as a defence. That resinous heartwood is agarwood, and the distilled oil is oud.
Why it is expensive
Only a small fraction of wild trees are ever infected, and it takes years for the resin to develop. Most modern oud comes from cultivated plantations where infection is induced deliberately.
- Wild Cambodian and Indian oud - sweet, deep, very expensive
- Cultivated Thai and Malaysian oud - sharper, more affordable
- Oud accords - synthetic reconstructions, no agarwood at all
Reading a blend
A harsh oud smells of the barnyard for the first twenty minutes. That is normal in a pure distillation and it settles. What should not happen is a flat, chemical sharpness that never resolves - that usually means a thin synthetic accord carrying the whole composition.