'Fiorente', Apennines, Italy. Photo: Prof. Alberto Santini
|Hybrid parentage||U. pumila S.10 × U. minor C. 02|
|Origin||IPP, Florence, Italy|
Ulmus 'Fiorente' is a hybrid cultivar derived from a crossing of the Siberian Elm Ulmus pumila clone S.10 with Ulmus minor C.02 by the Istituto per la Protezione delle Piante (IPP), part of the Italian National Research Council, in Florence. The cultivar was patented in 2006, and introduced to commerce in 2012.
'Fiorente' is monopodial, and of exceptionally rapid growth in a temperate climate. Mean growth during trials in the Northern Apennine on poor clay soils exceeded 1.0 m in height and 1.5 cm in trunk diameter per annum. The tree's habit is conical, with a pronounced apical dominance. The lateral growth on the current year's growth is very limited; the crown is therefore rather columnar. The alternate leaves are of a moderate size, < 8 cm long × < 5 cm broad. Generally lanceolate in shape, the leaves are rough on the upper surface and pubescent beneath; they remain green well into the autumn and are shed relatively late. The tree usually commences flowering in its fourth or fifth year, during late February in Italy. The sessile samarae are ovate, < 14 mm × 17 mm.
Pests and diseases
Tested by inoculation with the fungal pathogen, 'Fiorente' revealed a moderate resistance to Dutch Elm Disease, sustaining 32.3 % defoliation and 19.9 % dieback, on a par with Dutch cultivars such as 'Lobel' and 'Plantyn' released in the early 1970s. 'Fiorente' is resistant to Elm Yellows, while susceptibility to the elm leaf beetle Xanthogaleruca luteola is much the same as that of the Field Elm Ulmus minor.
In Italy, the cultivar's rapid growth has bestowed it with an economic importance as a hardwood timber tree. Introduced to southern England in 2007 by Butterfly Conservation, 'Fiorente' has proven intolerant of ponding over winter, while its growth rate elsewhere on clay and chalk has been only moderate, less than half that of its stablemates 'Morfeo' and 'San Zanobi'.  The tree is not known to have been introduced to North America or Australasia.
'Fiorente' translates as 'flourishing'.
- Grange Farm Arboretum, Sutton St. James, Spalding, UK. Acc. no. 693.
- Great Fontley Farm, Fareham, UK, Butterfly Conservation Elm Trials plantation, Home Field: J5, L5.
- Royal Botanic Garden Edinburgh, UK. Acc. no. 20080340
- Sir Harold Hillier Gardens, Ampfield, UK. Acc. no. 2008.0367
- Santini A., Fagnani A., Ferrini F., Ghelardini L., & Mittempergher L., (2007). Fiorente and Arno elm trees. HortScience June 2007, Volume 42, Issue 3, pp 712 – 714. American Society for Horticultural Science, Alexandria, VA 22314, USA. 
- Brookes, A. H. (2013). Great Fontley Elm Trial, 2013 Report. Butterfly Conservation, Lulworth, England.