English Elm
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 English Elms in Fitzroy Gardens, Melbourne.
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| Ulmus procera Salisb. |
English Elm Ulmus procera Salisb. (syn. U. minor var. vulgaris Richens) is found across most of southern England, in Spain and central Italy. DNA analysis has now identified the tree with the Atinian elm once widely used for training vines in Italy; a survey of genetic diversity of trees in Spain, Italy and the UK [1] revealed that the trees in the UK are clones, genetically identical to a single tree they theorise arrived with the Romans. Its introduction to Spain is recorded by the Roman agronomist Columella in his treatise De Re Rustica, written circa AD 50. Although there are no records of its introduction to England, it is now widely assumed that it too was imported by the Romans, a hypothesis supported by the discovery of pollen in an excavated Roman vineyard. U. coritana (Melville) found in the neighbourhood of Leicestershire has been sunk as a smooth-leaved variant.
The English Elm was once one of the largest and fastest-growing deciduous trees in Europe, often exceeding 40 m in height, with a trunk up to 2 m in diameter. The largest specimen ever recorded in England, at Forthampton Court, near Tewkesbury, was 46 m tall. The leaves are dark green, almost orbicular, <10 cm long, with an oblique base and toothed edges. Wind-pollinated, the small, reddish-purple flowers are without petals, and appear in early spring before the leaves. The tree does not produce fertile seed, and propagation is entirely by root suckers.
Only two mature English Elms still survive in England: the 'Preston Twins' at Preston Park in the centre of Brighton, protected by the city council's rigorous elm sanitization policy. Owing to its homogeneity, the tree has proven particularly susceptible to Dutch elm disease, but immature trees remain a common feature in hedgerows courtesy of the ability to sucker from roots. After about 20 years, these too become infected by the fungus and killed back to ground level. English Elm was the first elm to be genetically engineered to resist disease, at Abertay University, Dundee [2].
Some of the most significant remaining stands line the streets of Melbourne, Australia, protected by geography and quarantine from disease [3]. Several fine trees also survive in New York, notably the Hangman's Elm in Washington Square Park.
The English Elm was valued for many purposes, notably as water pipes from hollowed trunks, owing to its resistance to rot in saturated conditions. However, it is chiefly remembered for its aesthetic contribution to the English countryside, where it sometimes occurred in densities of over 1000 per square kilometre. "Its true value as a landscape tree may be best estimated by looking down from an eminence in almost any part of the valley of the Thames, or of the Severn below Worcester, during the latter half of November, when the bright golden colour of the lines of elms in the hedgerows is one of the most striking scenes that England can produce" [Elwes & Henry, 1913].
[edit] References
- Armstrong, J. V. & Sell, P. D. (1996). A revision of the British elms (Ulmus L., Ulmaceae): the historical background. Bot. J. Linn. Soc. 120: 39-50.
- Bean, W. J. (1981). Trees and shrubs hardy in Great Britain. Murray, London.
- Cogulludo-Agustin, M. A., Agundez, D. & Gil, L. (2000). Identification of native and hybrid elms in Spain using isozyme gene markers. Heredity, August 2000, vol. 85. Nature Publishing Group, London.
- Elwes, H. J. & Henry, A. (1913). The Trees of Great Britain & Ireland. Vol. VII. pp 1848-1929. Private publication. [4]
- Richens, R. H. (1983). Elm. Cambridge University Press.
- Stace, C. A. (1997). New Flora of the British Isles. Cambridge University Press.
- White, J. & More, D. (2002). Trees of Britain & Northern Europe. Cassell's, London.
