The

American Elm ''Ulmus americana'', generally known as the American elm or, less commonly, as the white elm or water elm, is a species of elm native to eastern North America, naturally occurring from Nova Scotia west to Alberta and Montana, and south to Flor ...

cultivar A cultivar is a type of cultivated plant that people have selected for desired traits and when propagated retain those traits. Methods used to propagate cultivars include: division, root and stem cuttings, offsets, grafting, tissue culture, ...

''Ulmus americana'' 'Morden' was

cloned Cloning is the process of producing individual organisms with identical or virtually identical DNA, either by natural or artificial means. In nature, some organisms produce clones through asexual reproduction. In the field of biotechnology, c ...

from a selection made by the Dominion Experimental Farm,

Morden Morden is a district and town in south London, England, within the London Borough of Merton, in the ceremonial county of Greater London. It adjoins Merton Park and Wimbledon to the north, Mitcham to the east, Sutton to the south and Worcester Pa ...

Manitoba Manitoba ( ) is a Provinces and territories of Canada, province of Canada at the Centre of Canada, longitudinal centre of the country. It is Canada's Population of Canada by province and territory, fifth-most populous province, with a population o ...

, in 1939 on account of its ability to withstand severe ice storms without breakage.

Description

Fast-growing and ultimately large, 'Morden' has been described as "rather coarse".

Pests and diseases

The tree is not known to have a resistance to

Dutch elm disease Dutch elm disease (DED) is caused by a member of the sac fungi (Ascomycota) affecting elm trees, and is spread by elm bark beetles. Although believed to be originally native to Asia, the disease was accidentally introduced into Americas, America ...

(see Cultivation). No other specific information available, but the species generally is moderately preferred for feeding and reproduction by the adult Elm Leaf Beetle ''

Xanthogaleruca luteola ''Xanthogaleruca luteola'', commonly known as the elm-leaf beetle, is a beetle species in the family Chrysomelidae that is native to Europe but invasive in other parts of the world.http://cisr.ucr.edu/elm_leaf_beetle.html - Center for Invasive Sp ...

'', and highly preferred for feeding by the Japanese Beetle ''

Popillia japonica The Japanese beetle (''Popillia japonica'') is a species of scarab beetle. The adult measures in length and in width, has iridescent copper-colored elytra and a green thorax and head. It is not very destructive in Japan (where it is control ...

'' in the United States. ''U. americana'' is the most susceptible of all the elms to

verticillium wilt Verticillium wilt is a wilt disease affecting over 350 species of eudicot plants. It is caused by six species of ''Verticillium'' fungi: ''V. dahliae'', ''V. albo-atrum'', ''V. longisporum'', ''V. nubilum'', ''V. theobromae'' and ''V. tricorpu ...

.Pegg, G. F. & Brady, B. L. (2002). ''Verticillium Wilts''. CABI Publishing.

Cultivation

The tree was first marketed by the Patmore Nurseries,

Brandon Brandon may refer to: Names and people *Brandon (given name), a male given name * Brandon (surname), a surname with several different origins Places Australia *Brandon, a farm and 19th century homestead in Seaham, New South Wales *Brandon, Q ...

, Manitoba, circa 1948. A specimen planted in the Longenecker Horticultural Gardens at the

University of Wisconsin–Madison Arboretum The University of Wisconsin–Madison Arboretum is a teaching and research facility of the University of Wisconsin–Madison and the site of historic research in ecological restoration. In addition to its in Madison, Wisconsin (located about fou ...

''Arboretum News'', Vol. 9, No. 1, January 1960. University of Wisconsin in 1956 had died by 1974 "probably from

"; no others are known to remain in cultivation.

References

{{Elm species, varieties, hybrids, hybrid cultivars and species cultivars , state=collapsed American elm cultivar Ulmus articles missing images Ulmus