Ulmus bergmanniana

''Ulmus bergmanniana'' C.K.Schneid., commonly known as Bergmann's elm, is a deciduous tree found across much of China in forests at elevations of 1500–3000 m.

Description

The tree is very closely related to the wych elm ''Ulmus glabra''; it can reach a height of with a wide-spreading crown, and a trunk of about 0.9 m d.b.h.Fu, L., Xin, Y. & Whittemore, A. (2002). Ulmaceae, in Wu, Z. & Raven, P. (eds) ''Flora of China'', Vol. 5 (Ulmaceae through Basellaceae). Science Press, Beijing, and Missouri Botanical Garden Press, St. Louis, USA.

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The bark is longitudinally fissured, and varies in colour from greyish-white to dark grey. The pubescent leaves range from Leaf shape, obovate to elliptic, less than long, and bluish-green when mature.White, J. & More, D. (2003). ''Trees of Britain & Northern Europe''. Cassell's, London. The perfect, wind-pollinated apetalous flowers are produced on second-year shoots in February, followed by generally obovate samarae <30 mm long by 14 mm width, the centre of the seed about 7 mm from the slightly notched apex. Branchlets do not possess the corky wings characteristic of many other elm species.

File:Ulmus bergmanniana samara.jpg, Samara of ''Ulmus bergmanniana''
File:Ulmus bergmanniana leaves 2.jpg, Leaves of ''Ulmus bergmanniana''
File:GFA U. bergmanniana.jpg, ''U. bergmanniana'', Grange Farm Arboretum

Pests and diseases

''U. bergmanniana'' has a moderate resistance to Dutch elm disease; in trials in Oklahoma it was also found to be eschewed by the elm leaf beetle '' Xanthogaleruca luteola'

but further north at the Morton Arboretum was moderately to highly preferred by the insect. The species is also susceptible to the elm leafminer.Grimshaw, J. & Bayton, R. (2009). ''New Trees - Recent Introductions to Cultivation''. RBG Kew, London.

Cultivation

The tree was introduced to the West in 1900. In trials in the USA it was found to propagate well, and also proved to be very winter hardy. The tree was one of 12 Chinese species under evaluation at the Morton Arboretum, Illinois, in 2009 by the late Dr George Ware.Dirr, M. (2009). 'Future Tree Selections'. ''Western'', Spring 2009,  p.8. Western Nursery & Landscape Association, St Joseph, Missour

/ref> There are no known cultivars of this taxon.

Subspecies & varieties

Two varieties are recognized: var. ''bergmanniana'' L.K.Fu, and var. ''lasiophylla'' C.K.Schneid..

Etymology

The species was named by Camillo Karl Schneider for his friend Carl Bergmann, who assisted in indexing the work in which it was published.Schneider, C.K. (1906-1912). ''Illustriertes Handbuch der Laubholzkunde''. Vol.2.  p.902. Gustav Fischer Verlag, Jena.

Accessions

;North America
*Brenton Arboretum, US.
* Chicago Botanic Garden, US. Planted in West Collections Area.
* Denver Botanic Gardens, US. No acc. no. available.
* Morton Arboretum, US
acc. no. 44-95
Obtained from Yunnan Province, China.
* United States National Arboretum, Washington, D.C., US. Acc. nos. 68997, 76216, 76217, 76242, 68977.

;Europe
* Grange Farm Arboretum, Lincolnshire, UK. Acc. no. 507
*Wijdemeren City Council, Netherlands. Elm collection. Planted 2013 Smeerdijkgaarde, Kortenhoef.

Nurseries

;Europe
*Pan-Global Plant

Frampton-on-Severn, Gloucestershire, UK.

References

External links

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{{Taxonbar, from=Q7879422

Elm species and varieties
Trees of China
Flora of China
Trees of Asia
Ulmus articles with images
bergmanniana