| U. glabra × U. pumila|
Ulmus × notha
Ulmus × arbuscula is a putative hybrid of Ulmus scabra (: glabra) and Ulmus pumila raised from seed collected from a large wych elm in the St. Petersburg Botanic Garden in 1902. A similar crossing was cloned (FL025) by the Istituto per la Protezione delle Piante (IPP), Florence, as part of the Italian elm breeding programme circa 2000.
Ulmus × arbuscula Wikipedia
The St. Petersburg tree bore leaves 17–75 mm long with 20 lateral nerves, side shoots <125 mm long and leader shoots <170 mm long, and was described as a shrubby tree with pleasing foliage and branches appearing quite decorative.
A specimen at the Ryston Hall, Norfolk, arboretum obtained from the Späth nursery in Berlin before 1914, was killed by the earlier strain of Dutch elm disease prevalent in the 1930s.
Two trees survive in eastern European arboreta. U. × arbuscula is not known to have been introduced to North America or Australasia.Europe
Butterfly Conservation Hants & IoW Branch elm trials, Cams Bay, Fareham, UK. One specimen of IPP clone FL025 planted circa 2005.
Grange Farm Arboretum, Sutton St James, Spalding, Lincolnshire, UK. Acc. no. 1097.
Hortus Botanicus Nationalis, Salaspils, Latvia. Acc. nos. 18093, 18094. Planted 1964, no details available.
Strona Arboretum, University of Life Sciences, Warsaw, Poland.