Himalayan Elm
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| Ulmus wallichiana Planch. |
The Himalayan Elm Ulmus wallichiana (syn. Kashmir Elm) is a mountain tree ranging from central Nuristan in Afghanistan, through northern Pakistan and the Kashmir, to western Nepal at elevations from 800 m to 3000 m. Although dissimilar in appearance, its common name is occasionally used in error for the Cherry Bark Elm Ulmus villosa, which is also endemic to the Kashmir, but inhabits the valleys, not the mountain slopes. The Himalayan Elm grows to 30 m tall, with a broad crown featuring several ascending branches. The bark of the trunk is greyish brown and longitudinally furrowed. The leaves are elliptic-acuminate, up to 13 cm long and 6 cm broad on petioles between 5 mm and 10 mm long. The samarae are usually orbicular, up to 13 mm in diameter. There are two subspecies, wallichiana and xanthoderma, and a variety, tomentosa, distinguished largely by variations in pubescence of the leaves and young stems. The species is named after the Danish botanist Nathaniel Wallich.
The species is closely related to the Wych Elm U. glabra, but has a high resistance to the fungus Ophiostoma himal-ulmi endemic to the Himalaya and the cause of Dutch elm disease there. Consequently the tree was investigated in 1960 as a suitable source of anti-fungal genes for use in the Dutch hybridization programme, with the result that a frost-resistant variety was selected for propagation and breeding in the Netherlands. It subsequently featured in a number of hybrids, starting with Dodoens and culminating in Lutèce.
Endemic to an impoverished region with no fossil fuel resources, U. wallichiana is heavily lopped for fuel, and also for fodder, leaving it in danger of extermination in some areas. Elsewhere however, it has been deliberately planted near villages and farmhouses. Recognizing its predicament, efforts have been made in India to conserve the tree by drying the seeds and placing them in refrigerated storage. The tree is not known to be in cultivation in the USA, but is grown in the UK at the Sir Harold Hillier Gardens in Hampshire, and at Brighton & Hove where it forms part of the NCCPG elm collection [1] held by the city council.
[edit] References
- Maunder, M. (1988). Plants in Peril, 3. Ulmus wallichiana (Ulmaceae). Kew Magazine. 5(3): 137-140. Royal Botanic Garden, Kew, London.
- Melville, R. & Heybroek, H. (1971). The Elms of the Himalaya. Kew Bulletin Vol. 26(1). Royal Botanic Garden Kew, London.
- Phartyal, S., Thapliyal, J., Nayal, J. & Joshi, G. (2003). Seed storage physiology of Himalayan Elm (U. wallichiana): an endangered tree species of tropical highlands. Seed Science & Technology Vol. 31. International Seed Testing Association (ISTA), Bassersdorf, Switzerland.
