''Ulmus glabra'' 'Nana'

Ulmus glabra 'Nana'
'Nana', Sir Harold Hillier Gardens, UK
Species Ulmus glabra
Cultivar 'Nana'
Origin Europe

The dwarf wych elm cultivar Ulmus glabra 'Nana', a very slow growing shrub that with time forms a small tree, is of unknown origin. It was listed in the Simon-Louis (Metz, France) 1869 catalogue as Ulmus montana nana.[1][2] Henry (1913), referring his readers to an account of the Kew specimen in the journal Woods and Forests, 1884,[3] suggested that it may have originated from a witch's broom. It is usually classified as 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.[4]

Not to be confused with Loudon's U. campestris nana (1838), a dwarf field elm "with small, narrow, rough leaves".[5]

Description

The tree rarely exceeds 5 m in height, but is often broader.[6] The dark green leaves are smaller than the wych type, 5–9 cm long, often with one or two cusp-like lobes either side of the apex.[7] The thick twigs, short petiole and diminutive samara with seed close to base, all point to U. glabra origin. A specimen at Kew was described by Henry as 'a slow-growing hemispherical bush that has not increased appreciably in size for many years'.[2] Green describes 'Nana' as growing some 60 cm in 10 to 12 years.[8]

Pests and diseases

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

Cultivation

The Späth nursery of Berlin marketed U. montana nana in the late 19th century.[9] It was introduced to the Dominion Arboretum, Ottawa, Canada, in 1898.[10] A 'Nana' appeared as U. nana, 'Dwarf American elm', a "very small" elm with compact habit, in Kelsey's 1904 catalogue, New York.[11] (Other European elms described as 'American' by various nurseries include 'Vegeta',[12] 'Scampstoniensis',[13][14] and 'Lutescens'.[2]) The tree is still occasionally found in arboreta and gardens in the UK, Europe and North America. It is not known in Australasia. 'Nana' remains in cultivation in Europe (see Nurseries).

A shrub elm sold in the Netherlands as U. 'Monstrosa' appears from its leaf and short petiole to be 'Nana',[15] while one cultivated in the Royal Botanic Garden Edinburgh in the early 20th century as 'Nana' appears from its leaf and long petiole to have been 'Monstrosa'.[16] 'Nana Monstrosa' was an old synonym of U. 'Monstrosa'.[17][7] The current RBGE 'Nana' is the authentic clone (2017).

Notable trees

The specimen of 'Nana' in the University Parks (North Walk), Oxford, has attained a height of about 6 m (2017).[18]

Synonymy

  • Ulmus scabra nana Dipp.[19]
  • Ulmus glabra 'Bush': Plant Buyer's Guide, ed. 5, 253, 1949, without description.

Accessions

North America
Europe

Nurseries

North America

None known

Europe

References

  1. ↑ Simon-Louis Catalogue, p. 97, 1869
  2. 1 2 3 Elwes, Henry John; Henry, Augustine (1913). The Trees of Great Britain & Ireland. 7. p. 1868.
  3. ↑ Woods and Forests, 1884, p.482
  4. ↑ 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.
  5. ↑ Loudon, John Claudius (1838). Arboretum et fruticetum Britannicum. 3. p. 1404. , p.1378
  6. ↑ White, J. & More, D. (2003) Trees of Britain & Northern Europe. Cassell's, London.
  7. 1 2 Krüssman, Gerd, Manual of Cultivated Broad-Leaved Trees & Shrubs (1984 vol. 3)
  8. ↑ Green, Peter Shaw (1964). "Registration of cultivar names in Ulmus". Arnoldia. Arnold Arboretum, Harvard University. 24 (6–8): 41–80. Retrieved 16 February 2017.
  9. ↑ Katalog (PDF). 108. Berlin, Germany: L. Späth Baumschulenweg. 1902–1903. pp. 132–133.
  10. ↑ Saunders, William; Macoun, William Tyrrell (1899). Catalogue of the trees and shrubs in the arboretum and botanic gardens at the central experimental farm (2 ed.). pp. 74–75.
  11. ↑ General catalogue, 1904 : choice hardy trees, shrubs, evergreens, roses, herbaceous plants, fruits, etc. New York: Frederick W. Kelsey. 1904. p. 18.
  12. ↑ Arboretum et Fruticetum Britannicum, 3: 1398, 1404
  13. ↑ Winchelsea, C.C. (1910). "Weeping trees". The gardeners' magazine. 53: 501.
  14. ↑ Anthony waterer's catalogue. 1880. p. 20.
  15. ↑ Photographs of plant sold as 'Monstrosa' in Holland: Herman Geers Dwarf & Miniature Plants,
  16. ↑ data.rbge.org.uk
  17. ↑ Rehder, Alfred. "Ulmaceae". Bibliography of cultivated trees and shrubs hardy in the cooler temperate regions of the Northern Hemisphere. Jamaica Plain, Massachusetts: The Arnold Arboretum of Harvard University. pp. 135–143. Retrieved 18 October 2017.
  18. ↑ parks.ox.ac.uk/tree/alpha.htm
  19. ↑ Späth, Ludwig (1930). Späth-Buch, 1720-1930. Berlin: Self published. pp. 311–313, 351–352.
  20. ↑ Johnson, Owen (ed.) (2003). Champion Trees of Britain & Ireland. Whittet Press, ISBN 978-1-873580-61-5.
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