English Elm

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{{Taxobox | color = lightgreen | name = English Elm | regnum = Plantae | divisio = Magnoliophyta | classis = Magnoliopsida | ordo = Rosales | familia = Ulmaceae | genus = Ulmus | species = U. minor | binomial = Ulmus minor var. vulgaris | binomial_authority = Richens }}

English Elm (Ulmus minor var. vulgaris, syn. U. procera) is found across most of southern England, Spain, and central Italy. DNA analysis has now identified the tree as the Atinian elm once widely used for training vines in Italy. 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 the tree was imported by the Romans, a hypothesis supported by the discovery of pollen in an excavated vineyard.

It was once one of the largest and fastest-growing deciduous trees in Europe, often exceeding 40m in height, with a trunk up to 2m in diameter. The largest specimen ever recorded in England, at Forthampton Court, near Tewkesbury, was 46m tall. It has dark green, oval leaves 3-10 cm long and 3-7 cm broad, with an oblique base and toothed edges. The flowers are small and reddish-purple, with no petals, produced in early spring before the leaves flush. Asexual, it never produces fertile seed, and propagation is almost entirely by root suckers.

Only two mature specimens still survive in England, at Preston Park in the centre of Brighton, protected by the city council's rigorous elm sanitization policy. Owing to its genetic homogeneity, English Elm has proven particularly susceptible to Dutch elm disease, but immature trees remain a common feature in hedgerows courtesy of its 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, in experiments at Abertay University, Dundee, but there are no plans to release trees into the countryside.

Some of the most significant remaining stands line the streets of Melbourne, Australia, where they are protected by geography and quarantine from this disease [1]. Several fine specimens also survive in New York, notably the Hangman's Elm in Washington Square.

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].

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References

  • 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, Edinburgh. [2]nl:Veldiep
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