Ulmus Cathedral

Ulmus 'Cathedral' is a hybrid elm cultivar developed at the University of Wisconsin–Madison, patented in 1994. It originated from a chance crossing between Japanese elm (female parent) and Siberian elm, with seed sent in 1958 by Prof. Nobuku Takahashi to Eugene Smalley. 'Cathedral' is a sibling of 'Sapporo Autumn Gold'. The tree is known for its weeping form and large elliptic leaves, measuring up to 14 cm long and 8 cm wide, similar to those of the Japanese elm. Mature leaves are spinach green, turning yellow and orange in autumn.

Tests in the U.S. show 'Cathedral' is less resistant to Dutch elm disease compared to other cultivars like 'New Horizon', though damage is typically limited to branch tips. French studies by INRA confirm it as moderately resistant. The leaves attract pests such as leaf hoppers and other piercing-sucking insects.

Cultivation requires high maintenance due to branch breakage issues. It is widely available in the U.S. and has been released commercially in Europe. The name 'Cathedral' was coined by Donald Willeke, inspired by the gothic arches formed when trees are planted in tight rows.

Accessions include North American arboretums like Brenton, Holden, and Morton, as well as Grange Farm Arboretum in the UK. Nurseries offering 'Cathedral' include Bailey Nurseries, Johnson's Nursery, and others in the U.S., and Future Forests in Ireland and Noordplant kwekerijen in the Netherlands.