Ulmus 'Cathedral' is a hybrid cultivar raised at University of Wisconsin–Madison (no. W44-25) patented in 1994. Arising from a chance crossing of the Japanese elm (female parent) and Siberian elm, seed was sent in 1958 by Prof. Nobuku Takahashi and his colleagues at the Sapporo Botanical Garden of Hokkaido University, Sapporo,Smalley, E. B. and Guries, R. P. Asian Elms: Sources of Disease and Insect Resistance, in Dunn, C P. (ed.). (2000).The Elms - Breeding, Conservation, and Disease Management. Springer Science + Business Media LLC., New York. to Eugene Smalley at Wisconsin–Madison;Smalley, E. B. & Lester, D. T. (1973). HortScience 8: 514–515, 1973.Smalley, E. B. & Guries, R. P. (1993). Breeding Elms for Resistance to Dutch Elm Disease. Annual Review of Phytopathology Vol. 31 : 325–354. Palo Alto, California. 'Cathedral' is thus a sibling of 'Sapporo Autumn Gold'.
Description The tree is distinguished by its weeping form and large elliptic leaves, < 14 cm long by < 8 cm broad, almost the same size and shape of those of its female parent, the Japanese Elm, spinach green when mature, turning yellow and orange in autumn. Santamour, J., Frank, S. & Bentz, S. (1995). Updated checklist of elm (Ulmus) cultivars for use in North America. Journal of Arboriculture 21 (3): 121-131. International Society of Arboriculture, Champaign, Illinois, US.
Pests and diseases Tests in the United States have found 'Cathedral' to be less resistant to Dutch elm disease than its WARF stablemates such as 'New Horizon', although damage is usually confined to the branch tips. Studies in France by the Institut National de la Recherche Agronomique (INRA) confirmed the tree as only 'moderately resistant'. The leaves are also favoured by leaf hoppers and other insects that feed by piercing and sucking.Giblin, C. P. & Gillman, J. H. (2006). Elms for the Twin Cities: A Guide for Selection and Maintenance. University of Minnesota.
Cultivation The tree requires relatively high levels of maintenance owing to its predilection for breaks occasioned by branch inclusions. 'Cathedral' is widely available across the United States, and has also been commercially released in Europe.
Etymology The tree was named by Mr Donald Willeke of Minneapolis, who observed that where planted in tight rows, a series of gothic cathedral-like arches was ultimately created between the trees.
Accessions North America Brenton Arboretum, US. 5 trees, acquired 2009. Acc. no. not known. Holden Arboretum, US. Acc. no. 91–202 Morton Arboretum, US. Acc. no. 205–2008, 30–2009 Europe Grange Farm Arboretum , Sutton St James, Spalding, Lincs., UK. Acc. no. 1058.
Nurseries North America Bailey Nurseries , St Paul, Minnesota, US. Johnson's Nursery , Menomonee Falls, Wisconsin, US. Lee Nursery Inc. , Fertile, Minnesota, US. Linder's Garden Center , St. Paul, Minnesota, US. Sherman Nurseries , Charles City, Iowa, US. Sun Valley Garden Centre , Eden Prairie, Minnesota, US. Europe Future Forests , Kealkill, Bantry, County Cork, Ireland. Noordplant kwekerijen , Glimmen, Netherlands.
References
External links https://www.extension.iastate.edu/Publications/SUL4.pdf Summary, inc. photographs, of elm cultivars resistant to Dutch elm disease available in the United States.