''Ulmus'' 'Lobel'

Ulmus 'Lobel'

'Lobel' elms, East Street, Brighton, UK.
Hybrid parentage '202' ('Exoniensis' × U. wallichiana) × '336' ('Bea Schwarz' selfed)
Cultivar 'Lobel'
Origin Wageningen, The Netherlands

Ulmus 'Lobel' is a Dutch hybrid cultivar raised at Wageningen, derived from a crossing of clone '202' ('Exoniensis' × U. wallichiana) with '336' ('Bea Schwarz', selfed), cloned in 1962 and released for sale in 1973.

Description

'Lobel' is a fastigiate, small-crowned, tree not unlike the pyramidal Hornbeam Carpinus betulus 'Fastigiata'.[1][2] The typically acuminate leaves are < 11 cm long × < 7 cm broad, and notably late to flush, rarely before mid-May.[3][4]

Pests and diseases

'Lobel' was rated 4 out of 5 ("good") in the Netherlands for its resistance to Dutch elm disease.[5] However, in trials conducted by the Istituto per la Protezione delle Piante, Italy, 'Lobel' suffered 50% defoliation and 35.5% dieback when inoculated with unnaturally high concentrations of the fungal pathogen, compared with 2.8% and 1.2% resp. for 'Sapporo Autumn Gold'.[6]

Owing to the U. wallichiana in its ancestry, young specimens of 'Lobel' proved particularly susceptible to elm yellows (phloem necrosis) in trials in Italy. [7]

Cultivation

Following the development and release of cultivars such as 'Columella' more resistant to Dutch elm disease, planting is no longer recommended wherever the disease is prevalent.[8] Sales in the Netherlands declined from over 12,000 in 1989 to 1,100 in 2004[9] .

However, 'Lobel' is particularly resistant to sea winds, and was accordingly planted in large numbers in the coastal provinces in The Netherlands and by Portsmouth City Council in the late 1980s, notably to replace the Huntingdon Elms lost in the Great Storm of 1987 along the Ladies' Mile on Southsea Common. There are also large plantings at Ealing and Primrose Hill, London, Brighton & Hove, and Havant. 'Lobel' was included in trials in Canberra, Australia started in 1988 but has not thrived in that environment.

'Lobel' was introduced to North America in 1991 when Heybroek donated material to the North Central Regional PI Station, Iowa State University, but the tree is not known to have been commercially released there.[10]

Etymology

The tree is named for Matthias de L'obel, the Flemish botanist also commemorated by the genus Lobelia.

Accessions

North America

Europe

References

  1. Heybroek, Hans M. (1983). Burdekin, D.A., ed. "Resistant elms for Europe" (PDF). Forestry Commission Bulletin (Research on Dutch elm disease in Europe). London: HMSO (60): 108–113.
  2. Heybroek, H. M. (1993). The Dutch Elm Breeding Program. In Sticklen & Sherald (Eds.) (1993). Dutch Elm Disease Research, Chapter 3. Springer Verlag, New York, USA
  3. Santini, A., Fagnani, A., Ferrini, F., Ghelardini, L., & Mittempergher, L. (2005). Variation among Italian and French elm clones in their response to Ophiostoma novo-ulmi inoculation. Forest Pathology, 25 (2005), 183-193, Blackwell Verlag, Berlin
  4. Photographs of 'Lobel' elm, leaves and samarae
  5. Heybroek, H. M., Goudzwaard, L, Kaljee, H. (2009). Iep of olm, karakterboom van de Lage Landen (:Elm, a tree with character of the Low Countries). KNNV, Uitgeverij. ISBN 9789050112819
  6. Santini, A, et al. (2002). 'San Zanobi' and 'Plinio' Elm trees. HortScience 37(7): 11391141, 2002.
  7. Mittempergher, L., (2000). Elm Yellows in Europe. In: The Elms, Conservation and Disease Management. 103119. Dunn C.P., ed. Kluwer Academic Press Publishers, Boston, USA.
  8. Burdekin, D. A. & Rushforth, K. D. (Revised by Webber J. F. 1996). Elms resistant to Dutch elm disease. Arboricultural Research Note 2/96. Arboricultural Advisory and Information Service, Alice Holt, Farnham, UK.
  9. Hiemstra, J.A. et al. (2007) Belang en toekomst van de iep in Nederland. Praktijkonderzoek Plant & Omgeving, Wageningen UR, Netherlands.
  10. Gibbs, J. N., Brasier, C. M., McNabb Jnr., H.S., and Heybroek, H. M. (1975). Further studies on the pathenogenicity in Ceratocystis ulmi. Europ. Journ. Forest. Path. 5 (3): 161174.
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