Ulmus 'Arno' is an Italian hybrid cultivar derived from a crossing of 'Plantyn' (female parent) with the Siberian Elm Ulmus pumila clone S.2. It was raised by the Istituto per la Protezione delle Piante (IPP) in Florence, and released in 2007. However, 'Arno' was not a commercial success; propagation had ceased by 2010, and it is no longer patent protected. 'Arno' was introduced to the UK in 2007 by Hampshire & Isle of Wight Branch, Butterfly Conservation, as part of an assessment of DED-resistant cultivars as potential hosts of the endangered White-letter Hairstreak.