Ulmus × viminalis

Ulmus × viminalis

× viminalis, Benalla Botanic Gardens, Australia
Details
Hybrid parentage U. minor subsp. minor × U. minor var. plotii
Origin England

Ulmus × viminalis Lodd. is an elm hybrid derived from the crossing U. minor subsp. minor Richens × U. minor var. plotii Druce . W. J. Bean says that the cultivar, which he calls U. 'Viminalis', is one form of a natural hybrid, U. × viminalis, that occurs from Essex to Oxfordshire.[1] According to Henry, this was the tree first described in 1677 by Robert Plot from specimens growing in an avenue and coppice at Hanwell near Banbury,[2] though the name 'Plot's Elm' was later given by George Claridge Druce not to this hybrid but to one of its parents.[3]

The tree was once commonly treated as a variety of Ulmus procera, before it was determined as a hybrid by Melville.[4]

Contents

Description

Bean's description, "a narrow-headed, rather slender tree", and Henry's "tree with ascending branches, pendulous branchlets, and sparse foliage", accord with what would be expected from a crossing of Plot Elm and Smooth-leaved Elm, and exactly match two graceful mature elms labelled U. minor subsp. minor × U. minor var. plotii in the Royal Botanic Garden, Edinburgh (2011). These have rather longer, and more, lateral branches than Plot Elm. Ulmus × viminalis is a slow-growing tree which can ultimately reach 20 m in height.[5] [6] Leaves vary according to U. minor subsp. minor parentage, from obovate-elliptic to narrowly-elliptic; they are deeply serrated, < 5.0 cm long, nearly symmetrical at the base and long-acuminate at the tip, with prominent white axil tufts on the undersides.[7] [8] The cultivar form can be mistaken for a variety of birch.[6] The tree has been likened to Zelkova × verschaffeltii.[9]

Pests and diseases

The cultivar is very susceptible to Dutch elm disease; a specimen at the Ryston Hall [3], Norfolk, arboretum, obtained from the Späth nursery in Berlin before 1914,[10] was killed by the earlier strain of Dutch elm disease prevalent in the 1930s. The U. minor subsp. minor × U. minor var. plotii hybrids in the Royal Botanic Garden, Edinburgh, have so far survived the current epidemic where most other elms in the collection have not. They produce copious suckers.

Cultivation

A few specimens survive in arboreta in the UK, USA, and Australia.

Synonymy

Accessions

North America

Europe

Australasia

References

  1. ^ Bean, W. J. (1988) Trees and shrubs hardy in Great Britain, 8th edition, Murray, London, p.659
  2. ^ Elwes, H. J. & Henry, A. (1913). The Trees of Great Britain & Ireland. Vol. VII. p.1906. Private publication. [1]
  3. ^ Wilkinson, Gerald, Epitaph for the Elm, London 1978, p.72
  4. ^ Green, P. S. (1964). Registration of cultivar names in Ulmus. Arnoldia, Vol. 24. Arnold Arboretum, Harvard University. [2]
  5. ^ Elwes, H. J. & Henry, A. (1913). The Trees of Great Britain & Ireland. Vol. VII. p.1906. Private publication.
  6. ^ a b Browne, D. J. (1846). The Trees of America. Harper & Brothers, New York.
  7. ^ Elwes, H. J. & Henry, A. (1913). The Trees of Great Britain & Ireland. Vol. VII. p.1906. Private publication.
  8. ^ Bean, W. J. (1988) Trees and shrubs hardy in Great Britain, 8th edition, Murray, London, p.659
  9. ^ Hilliers' Manual of Trees & Shrubs. (1977). David & Charles, Newton Abbot, UK.
  10. ^ Ryston Hall Arboretum catalogue, circa 1920
  11. ^ Johnson, Owen (ed.) (2003). Champion Trees of Britain & Ireland. Whittet Press, ISBN 9781873580615.