The

hybrid Hybrid may refer to: Science * Hybrid (biology), an offspring resulting from cross-breeding ** Hybrid grape, grape varieties produced by cross-breeding two ''Vitis'' species ** Hybridity, the property of a hybrid plant which is a union of two dif ...

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 ''Ulmus minor'' Mill., the field elm, is by far the most polymorphic of the European species, although its taxonomy remains a matter of contention. Its natural range is predominantly south European, extending to Asia Minor and Iran; its northern ...

''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. 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. Herbarium specimens from the Washington trees show less elongated, rounder leaves than those at Kew, with fewer vein-pairs (see 'External Links').

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 Lee may refer to: Name Given name * Lee (given name), a given name in English Surname * Chinese surnames romanized as Li or Lee: ** Li (surname 李) or Lee (Hanzi ), a common Chinese surname ** Li (surname 利) or Lee (Hanzi ), a Chinese ...

of Hammersmith in 1879 grew at Kew Gardens, where it attained a height of . Republished 2004 Cambridge University Press, In the United States specimens stood along The Mall in Washington D.C. among American Elms on either side of the Reflecting Pool (2009), 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
/ref> 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.

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, 2016''Ulmus'' × ''hollandica'' 'Dauvessei'; Conservation Foundation, conservationfoundation.co.uk
/ref> File:Possible Ulmus x hollandica 'Dauvessei' or 'Haarlemensis' (3).jpg, Seafield Place elm File:Bark of possible Ulmus x hollandica 'Dauvessei' or 'Haarlemensis'.jpg, Bole of same File:Leaves of possible Ulmus x hollandica 'Dauvessei'.jpg, Leaves of same, August File:Possible Ulmus x hollandica 'Dauvessei' or 'Haarlemensis' (4).jpg, Foliage, October File:AZ0002 Ulmus. Seafield Place (04).jpg, Samarae of same File:AZ0002 Ulmus. Seafield Place (05).jpg, Same, spring

Hybrid cultivars

'Dauvessei' was crossed with ''

Ulmus × hollandica ''Ulmus'' × ''hollandica'' Mill. , often known simply as Dutch elm, is a natural hybrid between Wych elm ''Ulmus glabra'' and field elm ''Ulmus minor'' which commonly occurs across Europe wherever the ranges of the parent species overlap. In Eng ...

'', ''

U. glabra ''Ulmus glabra'' Hudson, the wych elm or Scots elm, has the widest range of the European elm species, from Ireland eastwards to the Urals, and from the Arctic Circle south to the mountains of the Peloponnese and Sicily, where the species reaches i ...

'', 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.: Lavalléebr>''Arboretum Segrezianum'' 235, 1877
*''Ulmus montana'' var. ''Dauvessei'': George Nicholson (botanist), Nicholson, ''Kew Hand-List Trees and Shrubs'', 2: 139, 1896.

References

External links

Kew specimen

* Labelled ''Ulmus dauvessei''; Kew Gardens specimen (1936) * Labelled ''Ulmus'' × ''hollandica'' nm. ''dauvessei'' (Henry; 'type tree'); Kew Gardens specimen (1955)

Washington specimens

* 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) {{DEFAULTSORT:Ulmus x hollandica 'Dauvessei' Dutch elm cultivar Ulmus Ulmus articles missing images