Hortus Botanicus Leiden, Netherlands

Common name: Agarhout, Agarwood

Family: Thymelaeaceae (Mezereum family)

Distribution: Southeast Asia

IUCN Red list: Critically Endangered

Life form: Tree

Comments: Agarwood grows in the tropical forests of Southeast Asia. However, it can be hard to find as Aquilaria crassna is greatly threatened by illegal felling. The reason for this is that the tree produces a valuable resin. From this resin a fragrant oil is extracted, which can fetch up to 8,000 Euros per litre. In the past, its amazing fragrance was reserved for sheikhs and kings. Nowadays powdered agarwood is used in Japan for rituals and in traditional medicine, as an expensive incense.
Why then is agarwood not cultivated on a large scale? It is not easy, because the tree only produces resin when it has been infected by a particular fungus. It is a defence mechanism which ensures the fungus cannot cause too much harm. Aquilaria crassna can reach a height of 20 m. and grows in places where the sun can shine through the dense canopy of the forest. This species is evergreen and its waxy white flowers grow in racemes.