Ulmus ‘Sapporo Autumn Gold’
Family: Sapporo Autumn Gold Elm
AU. ‘Sapporo Autumn Gold’ was selected by Dr E. Smalley in Japan in the late 1950s. It is probably a hybrid of U. japonica and another Asiatic elm, and was selected because of its complete resistance to Dutch Elm Disease.
U. ‘Sapporo Autumn Gold’; is a medium-sized tree, growing to 15m, with annual growth up to 1000mm. When young, it is irregular in growth as with U. x hollandica, but with age it develops an oval canopy to 10m wide.
The foliage is intermediate in size between U. x hollandica and U. parvifolia, giving dense shade beneath. In autumn, it is bright gold, far richer than English Elm. The tree is fully deciduous, and the leaf litter is less problematic than with English Elm.
Apart from its resistance to Dutch Elm Disease (at present not in Australia), ‘Sapporo Autumn Gold’ was selected because of its superior form to other Asiatic elm species. Many of these Asiatic elms are very twiggy and weak-wooded; ‘Sapporo Autumn Gold’ tends to have much stronger wood and a less-twiggy canopy.
It will grow well in most sites, but thrives in areas where high-clay-fraction soils will hold reasonable amounts of water. It has a vigorous root system, and has proven itself planted in North American and British nature strips.
Typical mature height: 15m
Useful in: streetscapes, parks
Sites for best growth: fortnightly irrigation