Ulmus minor subsp. minor

Ulmus minor subsp. minor
Smooth-leafed Elm at East Coker, Somerset, 2008
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Rosids
Order: Rosales
Family: Ulmaceae
Genus: Ulmus
Species: U. minor
Subspecies: U. minor subsp. minor
Trinomial name
Ulmus minor subsp. minor
Richens
Synonyms
  • Ulmus campestris var. laevis Spach, Planch.
  • Ulmus campestris var. glabra Hartig, Planch., Aschers. & Graebn.
  • Ulmus carpinifolia Gled.
  • Ulmus foliaceae Gilibert, Sarg.
  • Ulmus glabra (not Huds.), Ley, Mill., Smith, Loudon, Rchb., Wilkomm, C. K. Schneid.
  • Ulmus micrantha Kitt.
  • Ulmus microphylla Mill.
  • Ulmus nitens Moench
  • Ulmus sparsa Dumrt.

Ulmus minor subsp. minor Richens, the Smooth-leaved Elm, Narrow-leafed Elm or East Anglian Elm, is a subspecies of the Field Elm native to southern Europe and Asia Minor including Iran.

The name Ulmus minor subsp. minor was used by R. H. Richens [1] for Field Elm that was not English Elm, Cornish Elm, Lock Elm or Guernsey Elm. Many publications, however, continue to use plain Ulmus minor for Richens's Ulmus minor subsp. minor. Indeed Dr Max Coleman of Royal Botanic Garden Edinburgh argued in his 2002 paper 'British Elms' that there was no clear distinction between species and subspecies.[2]

Description

The Smooth-leaved Elm is a deciduous tree that can grow to 35 m. Its Latin synonym carpinifolia alludes to the superficial similarity of the leaves to those of Hornbeam Carpinus sp., while the common names contrast the smooth upper surface and narrowness of the leaves with those of the Wych Elm, which are rough and broad.[3][4] The apetalous perfect wind-pollinated flowers, and fruit (samarae) are very similar to those of the species.

Pests and diseases

Although the Smooth-leafed Elm is generally susceptible to Dutch elm disease, it is genetically a highly variable tree and it is possible some specimens survive in the UK owing to an innately high level of resistance (see Cultivation). Research currently (2009) in hand by Cemagref at Le Pepiniére forestiére de l’Etat, Guémené-Penfao, France, should confirm this. However, all Smooth-leafed Elm varieties are believed to have been introduced into Britain from central and southern Europe during the Bronze Age,[5] and some, being beyond their natural climates and environments, may be growing slowly and thus producing smaller springwood vessels restrictive to the Ophiostoma fungus. Good performance in the field may also be owing to resistance to bark beetle feeding or breeding. Moreover, several types of this subspecies also have very pendulous twigs when mature, a factor which could also make them unattractive to foraging Scolytus beetles, which are disinclined to invert themselves.[6]

As the tree suckers readily, its genetic resources are not considered endangered.[7]

The subspecies has a moderate to high susceptibility to the elm leaf beetle Xanthogaleruca luteola , and a moderate susceptibility to Elm Yellows.[8]

Cultivation

Four great East Anglian elms, Ulmus minor subsp. minor, tower over an oak (left) and a two-storey house, Badingham, Suffolk, 1984
Narrow-leaved elms near Tillingham, Dengie peninsula, 2010

Many mature specimens still survive in England, notably in East Anglia.[9][10] Here, the elms on the isolated Dengie peninsula in Essex, still thriving in the 1980s when Professor Oliver Rackham made his study,[11] continue to fare better than most. The Woodland Trust currently lists (2013) some 120 surviving "ancient" smooth-leaved elms in England and Wales,[12] some of which are among the elms now being cloned, propagated and planted as part of The Conservation Foundation's 'Great British Elm Experiment' and 'Ulmus londinium' projects, a scheme to identify disease-resistant strains and return elms to city and countryside.[13][14]

In a more academically-based project, most of the clones of the surviving European Field Elms that have been tested since the 1990s for innate resistance to Dutch elm disease by national research institutes in the EU, with a view to returning Field Elm to cultivation in Europe,[15] would be classified by Richens’s system as Ulmus minor subsp. minor. Results from Spain (2013), for example, confirm that a very small number of surviving Field Elms (about 0.5% of those tested) appear to have comparatively high levels of tolerance of the disease, and it is hoped that a controlled crossing of the best of these will produce resistant Ulmus minor hybrids for cultivation.[16]

Narrow-leaved elm was occasionally planted as an ornamental urban tree.

Notable trees

The largest recorded tree in the UK grew at Amwell, Herts., measuring 40 m in height and 228 cm d.b.h. in 1911.[17] Another famous specimen was the great elm that towered above its two siblings at the bottom of Long Melford Green, Long Melford, Suffolk,[18] till the group succumbed to disease in 1978. The three "were survivors of a former clone of at least nine elms, one dating from 1757".[19] The Long Melford elms were painted in 1940 by the watercolourist S. R. Badmin in his 'Long Melford Green on a Frosty Morning', now in the Victoria and Albert Museum.[20]

The largest known surviving trees are at East Coker, Somerset (30 m high, 95 cm d.b.h.), Termitts Farm near Hatfield Peverel, Essex (25 m high, 145 d.b.h.), Scrub Wood near Little Baddow, Essex (30 m high), and Melchbourne, Bedfordshire, (147 cm d.b.h.).[21]

Cultivars

Hybrids

The tree's natural range in eastern England overlaps with that of Wych Elm (Ulmus glabra), the two species hybridizing to produce elms of the Ulmus × hollandica type. U. minor subsp. minor is believed to have hybridized also with Plot Elm to create Ulmus × viminalis.

Accessions

North America

Europe

Nurseries

North America

None known.

Europe

Australasia

References

  1. Richens, R. H., Elm (Cambridge 1983), p.280
  2. Coleman M. (2002) 'British elms.' British Wildlife 13 (6): 390-395.
  3. Stace, C. A. (1997). New Flora of the British Isles, 2nd edition. Cambridge University Press.
  4. White, J. & More, D. (2003). Trees of Britain & Northern Europe. Cassell's, London.
  5. Richens, R. H. (1983). Elm. Cambridge University Press.
  6. Webber, J. (2008). Dutch elm disease in Britain. Forest Research, Forestry Commission, Alice Holt, Farnham, Surrey
  7. 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 and Disease Management. Kluwer Academic Publishers, Boston, USA.
  8. Mittempergher, L. & Santini, A. (2004). The History of Elm Breeding. Invest. Agrar.: Sist Recur For. 2004 13 (1), 161-177.
  9. Miles, A. (2007) Hidden Trees of Britain. Ebury Press.
  10. Gibbs, J. N., Brasier, C. M., Webber, J. F. (1994) Dutch elm disease in Britain. Forestry Commission Research Note No. 252.
  11. Oliver Rackham, A History of the Countryside (London, 1986)
  12. The Woodland Trust, Tree Search,
  13. conservationfoundation.co.uk
  14. northamptonchron.co.uk
  15. Screening European Elms for resistance to 'Ophiostoma novo-ulmi' (Forest Science 2005)
  16. ‘Spanish Clones’ (Oct. 2013) resistantelms.co.uk,
  17. Elwes, H. J. & Henry, A. (1913). The Trees of Great Britain & Ireland. Vol. VII. 1848–1929. Republished 2004 Cambridge University Press, ISBN 9781108069380
  18. Photograph of the great elms on Long Melford Green (Francis Frith Collection, images.francisfrith.com)
  19. Photograph, plate XXI(h), in Oliver Rackham, A History of the Countryside (London, 1986), p.236.
  20. S. R. Badmin's 'Long Melford Green on a Frosty Morning', Victoria and Albert Museum
  21. Tree Register Of the British Isles (TROBI)
  22. "List of plants in the {elm} collection". Brighton & Hove City Council. Retrieved 23 September 2016.


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