|Scientific Name:||Taiwania cryptomerioides|
Taiwania flousiana Gaussen
|Taxonomic Notes:||The mainland Asian populations have frequently been referred to as Taiwania flousiana Gaussen. On the IUCN Red List, Taiwania is regarded as a monotypic genus.|
|Red List Category & Criteria:||Vulnerable A2cd ver 3.1|
|Assessor(s):||Thomas, P. & Farjon, A.|
|Reviewer(s):||Gardner, M. & Nguyen, T.H.|
This is a very long-lived tree which was undoubtedly more widely distributed 500 years ago (a time period which is possibly less than three generations ago). In the more recent past, it been heavily exploited for its valuable timber and there has been at least a 30-49% population reduction in that time. This is a minimum estimate, and it could well have been higher. The population is now largely stable across much of its range due to conservation efforts in Taiwan, the logging ban in China, and a community conservation programme in Viet Nam. The situation in Myanmar is uncertain as the full extent of its distribution in NE Myanmar is unknown. It is very likely that at least some stands have been logged within the last 25 years and that this is continuing. Based on current knowledge, Taiwania is assessed as Vulnerable. More detailed information from Myanmar could result in a reassessment of Endangered under B2ab(ii,iii,iv,v).
|Range Description:||In mainland China, this species is currently known from several localities on the divide between the Nu Jiang (Salween) in extreme NW Yunnan and SE Xizang [Tibet] as well as the Nmai in extreme NE Myanmar [Burma]. This current distribution reflects a recent history of intense exploitation within the last 100 years in the southern parts of the Gaoligong Mountains in China and Myanmar. A locality on the Nu Jiang - Jin Jiang divide needs further verification. In all other areas of China this species is very likely not indigenous. In Taiwan, its natural distribution is spread across the central mountains of the island. In Viet Nam it is only known from one locality in the southern part of the Hoang Lien Range. This was discovered in 2001.|
Native:China (Guizhou, Hubei, Sichuan, Yunnan); Myanmar; Taiwan, Province of China; Viet Nam
|Range Map:||Click here to open the map viewer and explore range.|
The Vietnamese population is estimated to be around 100 trees within an area of less than 3 km².
The Chinese population has been estimated to number 55,275 in three provinces although this includes trees from subpopulations in provinces apart from Yunnan that are not considered to be indigenous for the purposes of this assessment. It is also uncertain how many of these are mature individuals.
Accurate information on population size and trends for Myanmar is not available although extensive logging is known to have taken place on the western slopes of the Gaoligong mountains and in the area of the Nmai River. Given the high value of its timber, it is very likely that at least some subpopulations have recently been logged (Global Witness 2005, 2009).
The population in Taiwan is estimated to exceed 10,000 mature individuals, largely as a result of recent discoveries in SE Taiwan.
|Habitat and Ecology:||
Taiwania is a conifer of montane forests at altitudes from 1,750 m to 2,900 m asl.
In Taiwan it grows in the cool temperate coniferous forest belt with Chamaecyparis obtusa var. formosana and C. formosensis as codominant species and more scattered occurrence of Calocedrus formosana, Cunninghamia konishii, Picea morrisonicola, Pseudotsuga sinensis and Tsuga chinensis. Angiosperm trees are common but scattered, e.g. Castanopsis, Quercus and Trochodendron aralioides, while shrubs such as Camellia brevistyla, Eurya, Rhododendron, and Vaccinium are more abundant and the bamboo Yushania niitakayamensis can cover large areas.
In Yunnan and across the border in Myanmar [Burma] it occurs with Tsuga dumosa, Taxus wallichiana and Torreya grandis var. yunnanensis in the understorey. All the trees are densely hung with the lichen Usnea longissima and mosses and leafy liverworts cover trunks and branches. Some angiosperm trees are mixed in and become more abundant at lower altitudes, e.g. Acer, Castanopsis, Lithocarpus, Quercus, Magnolia, Schima and Sorbus, and in the understorey Rhododendron and many other shrubs are abundant.
In Viet Nam it is scattered in remnants of montane evergreen forest dominated by Fagaceae, Lauraceae and some Magnoliaceae, with only one other large conifer, Fokienia hodginsii, common.Throughout its distribution, Taiwania is an emergent, usually forming small groves in sheltered side valleys. It can attain an age of 1,600+ (probably over 2,000) years and belongs ecologically to those conifers which through longevity and canopy emergence survive all other forest trees, 'waiting' for episodal forest disturbance (most likely fire but possibly also landslides) to regenerate. The forest soils are yellow and red acidic derivatives of granitic or metamorphic rocks. The climate is strongly influenced by monsoons, with annual precipitation exceeding 4,000 mm in China, but at about 3,000 mm in Viet Nam. Reports of this species from other areas in China (Fu and Jin 1992, Flora of China 4 1999) do not refer to this type of extremely wet monsoon forest and it is very unlikely that Taiwania is indigenous there.
|Use and Trade:||
The wood of Taiwania is very durable and valued for timber; notable is the past use for coffin making. In Viet Nam the local H'Mong mountain people use it together with that of Fokienia hodginsii for their houses, in particular for roof planks. Some of this wood is beautifully marked with red and pale yellow annual rings (late and early wood) and prized for furniture. Plantation forestry using Taiwania is limited in Taiwan and more extensive in Guizhou and Hunan in mainland China; it will take many years before these are trees suitable for harvest as the species is (beyond sapling and pole stages) slow growing.This tree was introduced to Japan, Europe, North America, and New Zealand as an ornamental tree, where it grows well outside in temperate regions with none or only light frosts in winter and sufficient moisture. Despite its attractive form and foliage as a young tree, it has remained rare and is almost restricted to arboreta and botanic gardens.
|Major Threat(s):||In Yunnan many stands of old growth Taiwania were still exploited until recently; the logging ban now imposed by the government of China may have called a halt to this. In Taiwan the establishment of Yushan National Park in 1984 protected several natural stands of trees, but many had been felled by that time. In Viet Nam, the small population is Critically Endangered, because the forest remnants in which it still occurs are acutely threatened by deliberately set fires in the area to convert the forest to grazing lands. This subpopulation has also suffered from felling; it is estimated that perhaps as much as 80% of its habitat has already been destroyed (A. Farjon pers. obs. 2002). In Myanmar, extensive logging has occurred on the western slopes of the Gaoligong Mountains and it is highly likely that this species will have been targeted wherever possible due to the value of its timber.|
|Conservation Actions:||Some subpopulations of this species occur within protected areas. The Government of China has recently (in 2001) imposed a ban on all logging in China. In Taiwan it occurs in the Yushan National Park. In Viet Nam the population is currently not within a protected area, however, the provincial Forest Protection Department and Flora and Fauna International are currently working on a community based conservation project in an attempt to ensure its in-situ conservation. Seed collections aimed at providing material for restoration work as well as seed banking and utilization trials have been undertaken in Vietnam (Nguyen et al. 2004). Plantations and seed orchards have been established in Taiwan and to a more limited extent in Yunnan. A recently discovered large subpopulation (at least 10,00 mature individuals) in southern Taiwan is relatively secure due to its extreme inaccessibility and the fact that the whole area of the Holy Lake is considered as a Holy Land by the local people.|
|Citation:||Thomas, P. & Farjon, A. 2011. Taiwania cryptomerioides. The IUCN Red List of Threatened Species. Version 2015.2. <www.iucnredlist.org>. Downloaded on 06 July 2015.|