Golden Vietnamese cypress (Xanthocyparis vietnamensis)
|Size||Height: 10 - 15 m (1)|
The golden Vietnamese cypress is Classified as Critically Endangered on the IUCN Red List (1).
The highly endangered golden Vietnamese cypress (Xanthocyparis vietnamensis), known locally as ‘Bach Vang’, can reach a height of 15 metres, creating a giant bluish-green forest across the steep mountainous landscape where it occurs. When the tree is young the crown has a pyramidal shape, which becomes progressively more flattened as it grows (2).
The branches of the golden Vietnamese cypress are long and droopy, and interestingly, have both young and mature leaves on the same stem, which is an unusual characteristic. The young leaves are easily identified as they have a spiky appearance, in contrast with the scale-like mature leaves (2). The cones are small and whorl shaped (3).
The trunk of the golden Vietnamese cypress is 50 to 80 centimetres in diameter (2), and the soft bark is a red-brown colour. The bark on the branches is thinner than on the trunk, and exfoliates off in flakes, much like human skin (4).
The golden Vietnamese cypress was first discovered in 1999, in the secluded limestone mountains of the northern Vietnamese province of Ha Giang, north west of the Bat Dai Son nature reserve (2), and this is still the only known location (5). It has a very limited range of less than 50 square kilometres (1).
Found on steep-sided mountains in cloud forest (1), the golden Vietnamese cypress has a preference for wet soil, and the limestone ridges on which the tree is found are extremely eroded, containing little soil pockets that it takes root in (5). The climate is tropical, with temperatures ranging from 14 to 18 degrees Celsius, while also receiving high rainfall. This species can be found at elevations up to 1,330 metres (2).
Knowledge of the golden Vietnamese cypress is fairly limited, but it is assumed to have a similar biology to other species in the genus Cupressus, particularly its closest relative, the Nootka cypress (Cupressus nootkatensis) (6). The golden Vietnamese cypress is an evergreen species, so does not shed its leaves, but keeps them all year round (3).
The tree grows slowly and has a tendency to curve and contort around the ridges of the rocks it lives in (2). It is thought that, like the Nootka cypress, the golden Vietnamese cypress spreads its seeds using wind dispersal, with the tightly closed cones bursting open to release a shower of seeds that catch in the wind and may be carried some distance away. Once the seeds have been dispersed, they will not germinate until growing conditions are optimal. The seeds may remain dormant if there is not sufficient moisture and soil where they land (7).
Due to the expansion of agriculture in the local area, the habitat of the Golden Vietnamese cypress has been severely reduced, and it appears to have difficultly regenerating in the over populated area left available (2).
The golden Vietnamese cypress is also threatened by tree-felling and fires (8), with the local people known to use the wood of this species for housing and fuel (2).
There are currently no specific conservation measures in place to protect the golden Vietnamese cypress, although cuttings have been taken by a forestry nursery for propagation. The area where this species occurs is partly covered by a Provincial Forest Protected Area (1).
There are also plans to expand the Bat Dai Son nature reserve to include the habitat of this endangered plant. Within this nature reserve it is hoped to replant seedlings and cuttings in degraded limestone areas, where the golden Vietnamese cypress may have existed in the past (2).
For more information on the golden Vietnamese cypress and its conservation:
Global Trees Campaign - Golden Vietnamese cypress
This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
- Evergreen: a plant which retains leaves all year round. This is in contrast to deciduous plants, which completely lose their leaves for part of the year.
- Genus: a category used in taxonomy, which is below ‘family’ and above ‘species’. A genus tends to contain species that have characteristics in common. The genus forms the first part of a ‘binomial’ Latin species name; the second part is the specific name.
- Germinate: to begin to grow, usually following a period of dormancy and in response to favourable conditions. For example, the sprouting of a seedling from a seed.
- Whorl: in animals, a spiral or coil in the shell of a snail. In plants, a set of leaves, flowers, or branches that spring from a stem at the same point and encircle it.
IUCN Red List (August, 2011)
- Regalado Jr, J.C., Ke Loc, P., Tien Hiep, N., Thao, T.V. and Averyanov, L.V. (2006) The Vietnamese Golden Cypress (Xanthocyparis vietnamensis) Conservation Status Assessment (CSA) and Conservation Action Plan (CAP). Fauna and Flora International, Hoang Lien Son Project, Hanoi.
- Little, D., Schwarzbach, A., Adams, R. and Hsieh, C. (2004) The circumscription and phylogenetic relationships of Callitropsis and the newly described genus Xanthocyparis (Cupressaceae). American journal of Botany, 91: 1872-1881.
The Gymnosperm Database - Cupressus vietnamensis (August, 2011)
- Farjon, A., Tien Hiep, N., Harder, D., Ke Loc, P. and Averyanov, L.V. (2002) A new genus and species in Cupressaceae (Coniferales) from northern Vietnam, Xanthocyparis vietnamensis. Missouri Botanical Garden Press, 12(2): 179-189.
Electronic Atlas of the Plants of British Columbia - Chamaecyparis nootkatensis (August, 2011)
- Schmitz, N., Abrams, S. and Kermode, A. (2002) Changes in ABA turnover and sensitivity that accompany dormancy termination of yellow-cedar (Chamaecyparis nootkatensis) seeds. Journal of Experimental Botany, 53(366): 89-101.
- Farjon, A., Thomas, P. and Duc To Luu, N. (2004) Conifer conservation in Vietnam: three potential flagship species. Oryx, 38: 257-265.