The hybrid elm cultivar Ulmus × hollandica 'Dauvessei', one of a number of cultivars arising from the crossing of the Wych Elm U. glabra with a variety of Field Elm U. minor, is a very rare cultivar said to have originated at the D. Dauvesse nursery in Orléans, France before 1877.

Description According to Henry's description (1913) based on a tree at Kew, the branches ascend to form a broad, pyramidal crown; the leaves bear a resemblance to Wych Elm, but are generally smaller, rarely exceeding 10 cm long by 5 cm wide, and thinner in texture, with petioles nearly 1 cm long. Labelled Ulmus dauvessei; Kew Gardens specimen (1936); Labelled Ulmus × hollandica nm. dauvessei (Henry; 'type tree'); Kew Gardens specimen (1955) Krüssmann added that the leaf-base was more oblique.

The US National Arboretum, however, described the 'Dauvessei' that once grew in West Potomac Park, Washington, D.C., as similar in appearance to English Elm (in its lower latitude growth-form), forking at about 2 metres, reaching about 20 m tall by 18 m broad.Label of herbarium specimen WAG.1847155, Botany Catalogues, Naturalis Biodiversity Center. West Potomac Park specimen, Washington, D.C. Herbarium specimens from the Washington trees show less elongated, rounder leaves than those at Kew, with fewer vein-pairs. West Potomac Park specimen 1, Washington, D.C. (1966); "Herbarium specimen HUDC00010315" Howard University Herbarium; West Potomac Park, specimen 2, Washington, D.C. (1966); "Herbarium specimen HUDC00010316 Howard University Herbarium; West Potomac Park, specimen 3, Washington, D.C. (1966); West Potomac Park samara specimen, Washington, D.C. (1966)

Pests and diseases The tree is susceptible to Dutch elm disease.

Cultivation There are no confirmed surviving specimens of 'Dauvessei'. A tree obtained from Lee of Hammersmith in 1879 grew at Kew Gardens, where it attained a height of . Republished 2004 Cambridge University Press, Ulmus hollandica Dauvessei was present in The Hague in the 1930s.Christine Buisman, 'Verslag van de onderzoekingen over de iepenziekte, verricht in het phytopathologisch laboratorium Willie Commelin scholten te Baarn, gedurende 1932 (1)', Tijdschrift over Planteziekte, Vol 39 Iss 4, April  1933, p.85 In the United States specimens stood along The Mall in Washington D.C. among American elms on either side of the Reflecting Pool (2009),Sherald, James L., 'Elms of the Monumental Core' (Washington D.C.), National Park Service (2009),  p.7 West Potomac Park specimen 1, Washington, D.C. (1966) but it is not known whether any survive. A 2018 Cornell University study of the National Mall elms found five possible Ulmus × hollandica there (cultivar unidentified).Bassuk, Denig, Harada, Neal: 'The state of the elms on the National Mall in Washington, D.C.: tree & soil conditions' (2018); hort.cornell.edu A tree acquired from the Nobelius nursery in 1929 and grown at the University of Adelaide Waite Arboretum, Australia, died in 1997; Melville confirmed the 'Dauvessei' identification, reconfirmed by the arboretum in 1992.Information from Waite Arboretum, 2018, on accession no. 430, Ulmus × hollandica 'Dauvessei'

Putative specimen In the UK a broad pyramidal tree matching 'Dauvessei' descriptions and 'Dauvessei' herbarium material from a specimen in West Potomac Park, Washington, D.C., producing hybrid-type samarae, stands in the east corner of Claremont Park, Leith, by Seafield Place. Its location and tidy shape suggest a named cultivar.Google Maps: Seafield Pl - Google Maps (May 2015), accessdate: August 19, 2016Google Maps: Seafield Pl - Google Maps (July 2008), accessdate: August 19, 2016Ulmus × hollandica 'Dauvessei'; Conservation Foundation, conservationfoundation.co.uk

Hybrid cultivars 'Dauvessei' was crossed with Ulmus × hollandica, U. glabra, and U. minor in the Dutch elm breeding programme before World War II, but none of the progeny were of particular note and were discarded.Went, J. A. (1954). The Dutch elm disease - Summary of 15 years' hybridisation and selection work (1937–1952). European Journal of Plant Pathology, Vol 60, 2, March 1954.

Synonymy Ulmus campestris var. Dauvessi Hort.: Lavallée , Arboretum Segrezianum 235, 1877. Ulmus montana var. Dauvessei: Nicholson, Kew Hand-List Trees and Shrubs, 2: 139, 1896.

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