ironwood

Eusideroxylon is a genus of evergreen trees of the family Lauraceae. The genus is monotypic, and includes one accepted species, Eusideroxylon zwageri. The species is commonly known as Bornean ironwood, or by the Malay names belian and ulin. It is predominantly found in Borneo and Sumatra, where it grows in lowland rainforests, but may also occur in the Philippines. The Bornean ironwood is an extremely slow growing tree, reaching up to 50 metres (160 ft) in height, with trunks over 2 metres (6 ft 7 in) in diameter.

Eusideroxylon is classified as a hardwood tree, producing commercially valuable timber known for its high durability, as well as resistance to termites, rot, and fungi. This wood can last up to 100 years in contact with the ground. Due to extensive logging, it is listed as vulnerable in the IUCN Red List.