Taxus wallichiana

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Taxus wallichiana
Conservation status
Scientific classification
Kingdom: Plantae
Division: Pinophyta
Class: Pinopsida
Order: Pinales
Family: Taxaceae
Genus: Taxus
Species: T. wallichiana
Binomial name
Taxus wallichiana
Zucc.
Synonyms

Taxus baccata subsp. wallichiana
Taxus yunnanensis[1]

Himalayan Yew is a species of yew, native to the Himalaya from Afghanistan east to western Yunnan in southwestern China, at altitudes from 2,000–3,500 m.[2][3]

Growth[edit]

It is a medium-sized evergreen coniferous tree growing to 20 m tall, similar to Taxus baccata and sometimes treated as a subspecies of it. The shoots are green at first, becoming brown after three or four years. The leaves are thin, flat, slightly falcate (sickle-shaped), 1.5–2.7 cm long and 2 mm broad, with a softly mucronate apex; they are arranged spirally on the shoots but twisted at the base to appear in two horizontal ranks on all except for erect lead shoots. It is dioecious, with the male and female cones on separate plants; the seed cone is highly modified, berry-like, with a single scale developing into a soft, juicy red aril 1 cm diameter, containing a single dark brown seed 7 mm long. The pollen cones are globose, 4 mm diameter, produced on the undersides of the shoots in early spring.[3]

Species[edit]

Similar plants occurring further east through China to Taiwan, Vietnam and the Philippines are included in Taxus wallichiana as T. wallichiana var. chinensis (Pilger) Florin by some authors,[4] but are more often treated as a separate species Taxus chinensis.[2][3]

Medicinal uses[edit]

The tree has medicinal use in Ayurveda and Tibetan medicine. Taxus wallichiana is also a source of the chemical precursors to the anticancer drug paclitaxel.[5] Taxus wallichiana is used for making tea by the Bhotiya tribal community in the Garhwal Himalaya. The stem bark of this species, which is locally known as 'thuner' is collected for this purpose. This species is also used as fuelwood by the local communities.[6]

References[edit]

  1. ^ Flora of China
  2. ^ a b Farjon, A. (1998). World Checklist and Bibliography of Conifers. Royal Botanic Gardens, Kew ISBN 1-900347-54-7.
  3. ^ a b c Rushforth, K. (1987). Conifers. Helm ISBN 0-7470-2801-X.
  4. ^ Flora of China: Taxus wallichiana
  5. ^ Medicinal plants on verge of extinction - environment - 10 January 2009 - New Scientist
  6. ^ Kala, C.P. (2010). Medicinal Plants of Uttarakhand; Diveristy, Livelihood and Conservation. Delhi: BioTech Books. p. 188. ISBN 8176222097. 

Further reading[edit]

  • Gao, L. M., et al. "High variation and strong phylogeographic pattern among cpDNA haplotypes in Taxus wallichiana (Taxaceae) in China and North Vietnam." Molecular Ecology 16.22 (2007): 4684-4698.