Cupressus bhutanica

Maerki (2025)

Common names

Bhutan cypress, Tsenden (Maerki 2025).

Taxonomic notes

Lectotype Bhutan, Dewangiri (now called Deothang), Samdrup Jonghar District, 1838.01.06, Griffith 27 (K000088093). Synonyms Cupressus pendula Griff. (nom. illeg.), C. tortulosa Griff. (orth. var.). Phylogenetics unknown, but presumed to be closely related to the other Himalayan cypresses.

Maerki (2013) details the taxonomic complexities that enabled distinguishing the several taxa of eastern Himalayan Cupressus, concluding on C. tortulosa as the correct name for the Tsenden, the national tree of Bhutan. Unfortunately the nomenclatural committee for vascular plants then decided that "tortulosa" was an orthographic variant of "torulosa", and C. torulosa is a different species, the western Himalayan cypress. Thus C. tortulosa needed a new name, and C. bhutanica was selected.

Description

No description has been published, but several publications compare C. bhutanica (or C. tortulosa) to similar species. Due to the distinctive pendulous foliage, it can really be confused only with C. cashmeriana, C. corneyana, and C. funebris. C. funebris is clearly distinct due to small cones (8-15 mm diameter) with 6-8 scales. The following table (data from Maerki [2013]) will distinguish C. cashmeriana from C. bhutanica. Maerki (2025) compares C. corneyana to C. bhutanica and finds 60-72 seeds per cone and 5-7 seeds per scale in C. corneyana, vs. 104-120 and 9-11 for C. bhutanica. He also finds C. corneyana cones have a mean length of 16 mm, a mean diameter of 13 mm, and a mean length:diameter ratio of 1.2:1. Moreover, C. corneyana barely exists; there are only 5 known plants in the world, and they are all in European gardens.

Character	C. cashmeriana	C. bhutanica
Cones	Larger and serotinous; up to 14 scales; more seeds.	Smaller and not serotinous; up to 12 scales; fewer seeds.
Foliage	Glaucous-gray both in cultivation and in habitat.	Variable, in habitat bearing dark green foliage, in cultivation similar or glaucous-blue.
Pollen release in Europe	October.	January.

Distribution and Ecology

Bhutan, in the Punakha, Wangdue Phodrang, Lhuntse, and Trashigang Dzongkhags (districts). Grows on steep and rocky precipices at altitudes of 1800-2700 m on well-drained soils under cool, moist, temperate environmental conditions. One detailed study found an annual mean temperature of 16°C (8°C in January and 21.7°C in July), with a monsoonal summer-wet precipitation regime and 1377 m rainfall per year. The Tsenden is a light-demanding pioneer species, initiating primary forest succession and secondary succession following the destruction of broadleaf understory forests resulting from anthropogenic disturbances, episodic fires, or landslides. Common associates are primarily evergreen species and include Quercus, Castanopsis, Rhododendron, Betula, Alnus, Acer, Benthamedia, Sorbus, Rhus, Ilex, Symplocus, and Tsuga, sometimes with Pinus wallichiana and Quercus semecarpifolia in the overstory (Gurung et al. 2014).

The conservation status of "Near Threatened" is probably in error, as it conflates C. bhutanica and C. cashmeriana. Remaining natural forests are threatened by unsustainable rates of logging, although there is an effort underway to develop plantation forestry to meet the timber demand (Global Trees Campaign 2020).

Remarkable Specimens

This is among the largest species of cypress, with specimens known to have heights as great as 91 m and girths at breast height as great as 16 m. See examples here and here (accessed 2025.08.30). A brief report on the 91 m tree, which was 180 cm dbh when measured in 1995, is provided by Maerki (2025, p. 70).

Dallimore et al. (1967) report that "[a]lthough not well known in Britain, it is represented in the Temperate House at Kew. The most famous tree in Europe was that on the Isola Madre at Lake Maggiore. It was a specimen over 60 ft. high, of remarkable beauty" (note that they assessed this as C. cashmeriana, but it was assigned to C. bhutanica by Maerki [2025]).

Ethnobotany

This is the national tree of Bhutan, considered sacred in Bhutanese Buddhism and culture, and is commonly planted near temples and monasteries. The wood, as is common among Cupressus, is resistant to decay and suitable for woodworking, used for construction and furniture (Global Trees Campaign 2020).

Observations

No data as of 2026-01-28.

Remarks

The epithet refers to Bhutan, which includes the entire known wild distribution of this species.

Citations

Global Trees Campaign. 2020. Tsenden. https://www.bgci.org/wp/wp-content/uploads/2023/02/Tsenden-Global-Trees-PDF-version.pdf, accessed 2025.08.30.

Gurung, Dhan B., Yeshey Khandu, Om Katel, Purna B. Chhetri, and Pema Wangda. 2014. Population structure of Cupressus tortulosa Griffith along the altitudinal gradients of Tsendenanag Ridge in Punakha, Bhutan. Bhutan Journal of Natural Resources and Development 1(1):24-31.

Maerki, D. 2013. Which Latin name for the tsenden? Bulletin of the Cupressus Conservation Project 2(2):39-71, accessed 2025.08.30.

Maerki, Didier. 2025. Cupressus bhutanica, a new Latin name for the Tsenden. Bulletin of the Cupressus Conservation Project 14(2):59.