Urban (elm cultivar)
Encyclopedia
'Urban' is an American hybrid elm
Elm
Elms are deciduous and semi-deciduous trees comprising the genus Ulmus in the plant family Ulmaceae. The dozens of species are found in temperate and tropical-montane regions of North America and Eurasia, ranging southward into Indonesia. Elms are components of many kinds of natural forests...

 cultivar
Cultivar
A cultivar'Cultivar has two meanings as explained under Formal definition. When used in reference to a taxon, the word does not apply to an individual plant but to all those plants sharing the unique characteristics that define the cultivar. is a plant or group of plants selected for desirable...

 derived from progeny of a controlled crossing of the Siberian Elm
Siberian Elm
Ulmus pumila, the Siberian Elm, is native to Central Asia, eastern Siberia, Mongolia, Xizang , northern China, India and Korea . It is also known as the Asiatic Elm, Dwarf Elm and Chinese Elm. Two varieties are recognized: var pumila and var. arborea, the latter known as Turkestan elm...

 Ulmus pumila with the Dutch clone '148' (U. × hollandica 'Vegeta' × U. minor '28') in 1958 by Toru Arisumi of the USDA at Columbus
Columbus, Ohio
Columbus is the capital of and the largest city in the U.S. state of Ohio. The broader metropolitan area encompasses several counties and is the third largest in Ohio behind those of Cleveland and Cincinnati. Columbus is the third largest city in the American Midwest, and the fifteenth largest city...

, Ohio
Ohio
Ohio is a Midwestern state in the United States. The 34th largest state by area in the U.S.,it is the 7th‑most populous with over 11.5 million residents, containing several major American cities and seven metropolitan areas with populations of 500,000 or more.The state's capital is Columbus...

. Clone '148' had been sent to the USA from the Netherlands
Netherlands
The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

 by Johanna Went in 1952.

Description

Considered a poor ornamental, the tree is possessed of stiff branching and amorphous rounded form. The lanceolate
Leaf shape
In botany, leaf shape is characterised with the following terms :* Acicular : Slender and pointed, needle-like* Acuminate : Tapering to a long point...

 to obovate
Leaf shape
In botany, leaf shape is characterised with the following terms :* Acicular : Slender and pointed, needle-like* Acuminate : Tapering to a long point...

 leaves are < 9 cm long × < 4 cm broad, smooth with light venation on the upper surface, on 6 mm petioles
Petiole (botany)
In botany, the petiole is the stalk attaching the leaf blade to the stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called stipules. Leaves lacking a petiole are called sessile, or clasping when they partly surround the...

 and clustered on short, very thin, wingless branchlets.

Pests and diseases

'Urban' has a moderate resistance to Dutch elm disease
Dutch elm disease
Dutch elm disease is a disease caused by a member of the sac fungi category, affecting elm trees which is spread by the elm bark beetle. Although believed to be originally native to Asia, the disease has been accidentally introduced into America and Europe, where it has devastated native...

, and its foliage was adjudged "resistant" to Black Spot by the Plant Diagnostic Clinic of the University of Missouri
University of Missouri
The University of Missouri System is a state university system providing centralized administration for four universities, a health care system, an extension program, five research and technology parks, and a publishing press. More than 64,000 students are currently enrolled at its four campuses...

 http://soilplantlab.missouri.edu/plant/diseases/resistant.htm.
However, foliage can be heavily to severely damaged by the Elm Leaf Beetle Xanthogaleruca luteola
Xanthogaleruca luteola
Xanthogaleruca luteola, commonly known as the Elm Leaf Beetle, is a serious pest of the elm. Indigenous to Europe, it was accidentally introduced to North America. Both the imagines and larvae feed on the emergent leaves of the elm...

http://www.sunshinenursery.com/survey.htm

Cultivation

Noted for its tolerance of poor soils, pollution, and drought, 'Urban' was one of a number of elm hybrids assessed by the Forestry Commission
Forestry Commission
The Forestry Commission is a non-ministerial government department responsible for forestry in Great Britain. Its mission is to protect and expand Britain's forests and woodlands and increase their value to society and the environment....

 in the UK in the 1970s; half a dozen trees were among a batch of elms donated by the Commission in 1981 to reinforce a shelter belt at the Royal Bath & West
Royal Bath and West of England Society
The Royal Bath and West of England Society is a charitable society founded in 1777 to promote and improve agriculture and related activities around the West Country of England. Based at the Royal Bath and West of England Society Showground near Shepton Mallet in Somerset, the society is a...

 showground http://www.streetmap.co.uk/newmap.srf?x=362500&y=139500&z=3&sv=362500,139500&st=4&ar=N&mapp=newmap.srf&searchp=newsearch.srf&dn=716 south of Shepton Mallet
Shepton Mallet
Shepton Mallet is a small rural town and civil parish in the Mendip district of Somerset in South West England. Situated approximately south of Bristol and east of Wells, the town is estimated to have a population of 9,700. It contains the administrative headquarters of Mendip District Council...

 http://www.streetmap.co.uk/newmap.srf?x=363080&y=140120&z=5&sv=363080,140120&st=4&ar=Y&mapp=newmap.srf&searchp=newsearch.srf&dn=716. All these trees initially grew strongly on the heavy clay loam, attaining > 8 m in height in seven years. However, at this age, one died of Dutch Elm Disease
Dutch elm disease
Dutch elm disease is a disease caused by a member of the sac fungi category, affecting elm trees which is spread by the elm bark beetle. Although believed to be originally native to Asia, the disease has been accidentally introduced into America and Europe, where it has devastated native...

 whilst four others exhibited weakness at the root and fell in gales in later years . Only one tree remains (the TROBI
The Tree Register
The Tree Register, or more fully, the Tree Register of the British Isles , is a registered charity collating and updating a database of notable trees throughout Britain and Ireland...

 champion); 12 m high, 26 cm d.b.h. in 1997 , and that in poor health in 2008. The trees are survived by numerous root suckers however.

Other plantings in Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

 are few and far between; several were established in the port area of Amsterdam
Amsterdam
Amsterdam is the largest city and the capital of the Netherlands. The current position of Amsterdam as capital city of the Kingdom of the Netherlands is governed by the constitution of August 24, 1815 and its successors. Amsterdam has a population of 783,364 within city limits, an urban population...

 http://www.amsterdambomen.nl. The tree also featured in trials http://www.netspace.net.au/~stephenf/Resistant_Elms.html, in
Canberra
Canberra
Canberra is the capital city of Australia. With a population of over 345,000, it is Australia's largest inland city and the eighth-largest city overall. The city is located at the northern end of the Australian Capital Territory , south-west of Sydney, and north-east of Melbourne...

, Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

 started in 1988 but "has not shown promise in that environment".

Hybrid cultivars

'Urban' was crossed with the Wilson's Elm (now treated as Japanese Elm
Japanese Elm
Ulmus davidiana var. japonica, the Japanese Elm, is one of the larger and more graceful Asiatic elms, endemic to much of continental north-east Asia and Japan.-Description:...

 U. davidiana var. japonica) cultivar 'Prospector' to create the cultivar 'Patriot'
Ulmus 'Patriot'
The hybrid elm cultivar Patriot is a United States National Arboretum introduction derived in 1980 from a crossing of the American hybrid 'Urban' with the Wilson's Elm cultivar 'Prospector' and released to commerce, free of patent restrictions, in 1993...

.

Synonymy

  • 'Delaware No. 1': USDA, before commercial release as 'Urban'.
  • 'Ohio Hybrid': Santamour, F. S., & Bentz, S. E. Updated checklist of elm (Ulmus) cultivars for use in North America. Journal of Arboriculture, 21(3): May, 1995.

Accessions

North America
  • Chicago Botanic Garden
    Chicago Botanic Garden
    Located at 1000 Lake Cook Road, Glencoe, Illinois, USA, the Chicago Botanic Garden is a living plant museum situated on nine islands featuring 24 display gardens and surrounded by four natural habitats: McDonald Woods, Dixon Prairie, Skokie River Corridor, and Lakes and Shores. The Garden is open...

    , Glencoe
    Glencoe, Illinois
    Glencoe is a village in Cook County, Illinois, United States. As of the 2010 census, the village population was 8,723. Glencoe is located on suburban Chicago's North Shore. Glencoe is located within the New Trier High School District. Glencoe is regarded as one of the most affluent suburbs on...

    , Illinois
    Illinois
    Illinois is the fifth-most populous state of the United States of America, and is often noted for being a microcosm of the entire country. With Chicago in the northeast, small industrial cities and great agricultural productivity in central and northern Illinois, and natural resources like coal,...

    . 1 tree, in West Collections Area, listed as U. × hollandica 'Urban'.
  • Morton Arboretum
    Morton Arboretum
    The Morton Arboretum, in Lisle, Illinois, covers 1,700 acres and is made up of gardens of various plant types and collections of trees from specific taxonomical and geographical areas. It includes native woodlands and a restored Illinois prairie. The Arboretum has over 4,100 different species of...

    . Acc. no. 66-70

Europe
  • Brighton & Hove
    Brighton & Hove
    Brighton and Hove is a unitary authority area and city on the south coast of England. It is England's most populous seaside resort.In 1997 Brighton and Hove were joined to form the unitary authority of Brighton and Hove, which was granted city status by Queen Elizabeth II as part of the millennium...

     City Council, NCCPG elm collection http://www.brighton-hove.gov.uk/index.cfm?request=c1108042.
  • Grange Farm Arboretum
    Grange Farm Arboretum
    The Grange Farm Arboretum is a small private arboretum comprising 3 hectares accommodating over 800 trees, mostly native and ornamental species or cultivars, notably oaks, ashes, walnuts and elms, growing on a calcareous loam....

     http://www.thegardeningwebsite.co.uk/grange-farm-plants-speciality-rare-trees-shrubs-i411.html, Sutton St. James, Spalding
    Spalding, Lincolnshire
    Spalding is a market town with a population of 30,000 on the River Welland in the South Holland district of Lincolnshire, England. Little London is a hamlet directly south of Spalding on the B1172 road....

    , Lincs.
    Lincolnshire
    Lincolnshire is a county in the east of England. It borders Norfolk to the south east, Cambridgeshire to the south, Rutland to the south west, Leicestershire and Nottinghamshire to the west, South Yorkshire to the north west, and the East Riding of Yorkshire to the north. It also borders...

    , UK. Acc. no. 824.

Nurseries

North America
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