The Vietnamese Golden Cypress was only discovered in 1999, on a high ridge in the mountains of northern Vietnam, and subsequently described in 2002. The discovery caused great excitement: not only was it a species new to science, but it was considered different enough to be placed in its own genus Xanthocyparis however, since then, the species has been revised into the genus Cupressus.
Known locally as Bach vang, the Vietnamese Golden Cypress grows to 10-15m high with a diameter of up to 50-80cm. It has a pyramidal shape when young and a broad, flattened crown when mature.
The species is believed to have a very limited range in the mountains of northern Vietnam, close to the border with China. In 2012, one individual was found in Guangxi Province, China. Additional surveys in China in 2014, supported by the Global Trees Campaign, found 17 new individuals of this species: 15 adult trees and 2 seedlings. This indicates that the trees are capable of regeneration in the wild. This discovery brings the total number of known trees in China to 18. In addition to this, a GTC survey found 15 mature trees in Vietnam, 70km away from the original population of between 500 and 1000 individuals.
Cutting of the tree for timber is thought to be the most serious threat to this species. The timber is very hard and scented so is an attractive material for local construction. However, most trees are relatively small and contorted and this, combined with the difficulty of transporting timber from inaccessible habitat areas, limits its attractiveness for wider timber trade. There is some evidence that it has been cut for firewood in some areas.
As the species is only found on high, inaccessible ridges, the threat from agricultural expansion is limited. The tree has not been found in intact forest on lower slopes within its range, so it is believed to be naturally confined to the higher altitudes, making it susceptible to climate change. The tree is very slow growing and although regeneration has been recorded in the wild, it is thought to be limited.
As this species is only recently discovered, it is only reported in a limited number of botanic garden and arboreta collections. The Global Survey of Ex situ Conifer Collections (Shaw and Hird, 2014) reports that this species is only represented in 17 collections worldwide, but all of these trees are grown from cuttings making them clones.
The Global Trees Campaign has been working to protect and restore rare trees in northern Vietnam since 2005. Read about our current work here. Recently, Bedgebury Pinetum has been successful in growing these trees from seed, giving hope to this rare species.
Did you know?
‘Dragon blood’, a resin from the Socotran Dragon tree (Draceana cinnabari), was used and traded by the Roman empire as a medicine as early as the 1st Century BC.