Ulmus wallichiana subsp. wallichiana
Encyclopedia
Ulmus wallichiana subsp. wallichiana Melville & Heybroek was identified by Melville
Ronald Melville
Ronald Melville was an English botanist, based at the Royal Botanic Gardens Kew. He is chiefly remembered for his wartime research into rosehips as a source of vitamin C, prompted by the epidemic of scurvy amongst children owing to the reduced importation of fresh fruit...

 and Heybroek
Hans M. Heybroek
Hans M. Heybroek is a Dutch botanist best known for his researches into the genus Ulmus at the Dorschkamp Research Institute for Forestry & Landscape Planning. Until his retirement in 1992, he was responsible for the raising and release of numerous elm hybrid cultivars, notably 'Columella'...


after the latter's expedition to the Himalaya in 1960.

Description

A deciduous tree growing to 30 m with a crown comprising several ascending branches. The bark of the trunk is grey-brown, furrowed longitudinally. The leaves range from 6 to 13 cm long by 2.5 to 6 cm broad, elliptic-acuminate in shape, and with a glabrous upper surface, on petioles
Petiole (botany)
In botany, the petiole is the stalk attaching the leaf blade to the stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called stipules. Leaves lacking a petiole are called sessile, or clasping when they partly surround the...

 5 to 10 mm long. The samara
Samara (fruit)
A samara is a type of fruit in which a flattened wing of fibrous, papery tissue develops from the ovary wall. A samara is a simple dry fruit and indehiscent . It is a winged achene...

e are orbicular to obovate, 10 to 13 mm in diameter, the seed central.

Pests and diseases

The tree has a high resistance to the fungus Ophiostoma himal-ulmi endemic to the Himalaya and the cause of Dutch elm disease
Dutch elm disease
Dutch elm disease is a disease caused by a member of the sac fungi category, affecting elm trees which is spread by the elm bark beetle. Although believed to be originally native to Asia, the disease has been accidentally introduced into America and Europe, where it has devastated native...

there.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK