European White Elm

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European White Elm

European White Elm in winter

Conservation status

Least Concern

Scientific classification

Kingdom:	Plantae
Division:	Magnoliophyta
Class:	Magnoliopsida
Order:	Rosales
Family:	Ulmaceae
Genus:	Ulmus
Species:	U. laevis

Binomial name

Ulmus laevis
Pall.

Synonyms

Ulmus ciliata Ehrh.

Ulmus effusa Willd., Loudon, Willkomm, Fliche

Ulmus laevis var. celtidea Rogowicz

Ulmus laevis var. simplicidens (E. Wolf) Grudz.

Ulmus octandra Schkuhr

Ulmus pedunculata Foug.

Ulmus racemosa (not Thomas), Borkh.

The European White Elm Ulmus laevis Pall. is a large tree native to Europe, from France northeast to southern Finland, and southeast to Bulgaria and the Crimea; there is also a disjunct population in the Caucasus. Essentially a riparian species, it is most commonly encountered along rivers such as the Volga and Danube. It is the only elm tolerant of waterlogged ground, its massive shallow root system forming distinctive high buttresses around the base of the trunk.

Like other European elms, it has little innate resistance to Dutch elm disease, but is eschewed by the vector bark beetles and only rarely becomes infected. Its decline in Europe is chiefly owing to woodland clearance in river valleys.

European White Elm leaves and seeds

European White Elm flowers; note the long stems

Similar in stature to the Wych Elm, it typically reaches a height of over 30m and a trunk diameter of up to 2 m. The leaves are deciduous, alternate, simple ovate with a lop-sided base, < 10 cm long and < 7 cm broad, rough above, and downy underneath. The flowers appear before the leaves in early spring, produced in clusters of 15-30 together; they are 3-4 mm across on 20 mm long stems, have no petals and are wind-pollinated. The fruit is a winged samara 15 mm long and 10 mm broad with a single round 5 mm seed maturing in late spring.

The tree is distinguished from other European elms by the long flower stems, and is most closely related to the American Elm U. americana, from which it differs mainly in the irregular crown shape and frequent small sprout stems on the trunk. The species was never widely introduced to the USA, but is represented at several arboreta; there is also a notable specimen in Portland, Oregon. In the Far East, the tree has been planted in Xinjiang and elsewhere in Northern China; planting in Tongliao City is known to have been particularly successful. The tree is not known to have been introduced to Australasia. Examples in the UK are few and far between, but sometimes of great age. Several old trees survive amid diseased native elm near Torpoint in Cornwall [1]; others are found in Edinburgh, London (Peckham and Tooting), Brighton & Hove, and near St. Albans, Hertfordshire. A particularly fine tree stands in the village of Alfriston, East Sussex. However, in recent years, the tree has enjoyed a small renaissance in England. A popular larval host plant of the White-letter Hairstreak Satyrium w-album butterfly across Europe, the elm is now being planted by Butterfly Conservation and other groups to restore local populations decimated by the effects of Dutch elm disease on native or archaeophytic elms. The Cheshire Wildlife Trust, for example, is to plant 1,000 White Elms on its reserves in the Vale Royal district of the county.

European White Elm, Alfriston, East Sussex, UK (2006)

1 Cultivars
2 Hybrid cultivars
3 Arboreta etc. accessions
- 3.1 North America
- 3.2 Europe
4 Nurseries
- 4.1 North America
- 4.2 Europe
5 References
6 External links

[edit] Cultivars

Compared with the other European species U. glabra and U. minor, U. laevis has received scant horticultural attention, there being only five recorded cultivars, none of which are known to survive (2006): Aureo-Variegata, Colorans, Ornata, Punctata, Urticaefolia.

[edit] Hybrid cultivars

Unlike the other European species, laevis does not hybridize naturally, and the few reported instances of artificial hybridization in the 19th century are now regarded with suspicion.

[edit] Arboreta etc. accessions

[edit] North America

Arnold Arboretum, acc. nos. 17910, 637-79, 6951, 753-80.
Brenton Arboretum, Dallas Center, Iowa. No details available.
Dominion Arboretum, Canada. No details available
Longwood Gardens, acc. nos. 1964-0568, 1964-1119.
Morton Arboretum acc. nos. 1302-27, 446-48, 492-64, 27-98.

[edit] Europe

Brighton & Hove City Council, UK, NCCPG Elm Collection.
Copenhagen University, Botanic Garden. No details available.
ELTE Botanic Garden Budapest, acc. nos. 1998-0718, 1998-0719.
Great Fontley Farm, Fareham, UK, acc. nos. Platts 4, 5.
Hortus Botanicus Nationalis, Salaspils, Latvia acc. nos. 18136, 18140.
Royal Botanic Gardens Kew, UK, acc. nos. 1969-17302, 1973-11712.
Royal Botanic Gardens, Wakehurst Place, UK, acc. no. 1973-21048.
Royal Horticultural Society Gardens, Wisley, UK. No details available.
Sir Harold Hillier Gardens, UK, acc. no. 1981-2446.
Thenford House arboretum, Oxfordshire, UK. No details available.

[edit] Nurseries

[edit] North America

None known

[edit] Europe

Crown Nursery, Woodbridge, Suffolk, UK. [2].
Dulford Nurseries, Cullompton, Devon, UK. [3].

[edit] References

Bean, W. J. (1981). Trees and shrubs hardy in Great Britain, 7th edition. Murray, London.
Brookes, A. H. (2006). An evaluation of disease-resistant hybrid and exotic elms as larval host plants for the White-letter Hairstreak butterfly Satyrium w-album, Part 1. Butterfly Conservation, Lulworth, UK.
Collin, E., Bilger, I., Eriksson, G., & Turok, J. (2000). The conservation of elm genetic resources in Europe. In Dunn, C. P. (Ed.) (2000). The elms: breeding, conservation & disease management. Kluwer Academic Publishers, Boston.
Elwes, H. J. & Henry, A. (1913). The Trees of Great Britain & Ireland. Vol. VII. pp 1848-1929. Private publication. [4]
More D. & White, J. (2003). The Trees of Britain & Northern Europe, Cassell's, London.