Ulmus 'Nana'

Ulmus

'Nana', Sir Harold Hillier Gardens, UK
Cultivar 'Nana'
Origin Europe

The elm cultivar 'Nana' is a very slow growing shrub that with time forms a small tree. It was believed for many years to be a form of Ulmus glabra and is known widely as the 'Dwarf Wych Elm'. However, the ancestry of 'Nana' has been disputed in more recent years, Melville considering the specimen once grown at Kew to have been a cultivar of Ulmus × hollandica.[1]

Description

'Nana' leaves
'Nana' in winter, Kew

The tree rarely exceeds 5 m in height, but is often broader.[2][3] The dark green leaves are smaller than the type, < 11 cm long by 8 cm broad. Green[4] describes it as a very distinct variety not growing above 2 feet (60 cm) in 10 to 12 years. A specimen at Kew was described by Henry as 'a slow-growing hemispherical bush that has not increased appreciably in size for many years'.[5]

Pests and diseases

The low height of the tree should ensure that it avoids colonization by the Scolytus bark beetles and thus remain free of Dutch elm disease.

Cultivation

The tree is still occasionally found in arboreta and gardens in the UK, and has been introduced to North America and continental Europe; it is not known in Australasia.

Notable trees

The specimen of 'Nana' in the University Parks (North Walk), Oxford, has attained a height of 6 m (2014).[6]

Synonymy

Accessions

North America
Europe

Nurseries

North America

None known

Europe

References

  1. Melville, R. (1978). On the discrimination of species in hybrid swarms with special reference to Ulmus and the nomenclature of U. minor (Mill.) and U. carpinifolia (Gled.). Taxon 27: 345-351.
  2. Bean, W. J. (1981). Trees and shrubs hardy in Great Britain, 7th edition. Murray, London.
  3. White, J. & More, D. (2003) Trees of Britain & Northern Europe. Cassell's, London.
  4. Green, P. S. (1964). Registration of cultivar names in Ulmus. Arnoldia, Vol. 24. Arnold Arboretum, Harvard University.
  5. Elwes, H. J. & Henry, A. (1913). The Trees of Great Britain & Ireland. Vol. VII. pp 1848-1929. Private publication
  6. parks.ox.ac.uk/tree/alpha.htm
  7. Johnson, Owen (ed.) (2003). Champion Trees of Britain & Ireland. Whittet Press, ISBN 978-1-873580-61-5.