''Ulmus'' 'Regal' is an American

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 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 ...

developed by the

University of Wisconsin–Madison A university () is an institution of higher (or tertiary) education and research which awards academic degrees in several academic disciplines. Universities typically offer both undergraduate and postgraduate programs. In the United Stat ...

and released in 1983. 'Regal' was derived from seeds arising from the crossing of the Dutch hybrid clones 'Commelin' and '215' (''

Ulmus pumila ''Ulmus pumila'', the Siberian elm, is a tree native to Asia. It is also known as the Asiatic elm and dwarf elm, but sometimes miscalled the 'Chinese Elm' ('' Ulmus parvifolia''). ''U. pumila'' has been widely cultivated throughout Asia, No ...

'' × 'Hoersholmiensis') sent in 1960 by Hans M. Heybroek of the Dorschkamp Research Institute for Forestry & Landscape Planning,

Wageningen Wageningen () is a municipality and a historic city in the central Netherlands, in the province of Gelderland. It is famous for Wageningen University, which specialises in life sciences. The municipality had a population of in , of which many ...

, Netherlands.

Description

'Regal' has a strong central leader bestowing an upright columnar form similar to 'Commelin', making it particularly suitable for street planting.Santamour, J., Frank, S. & Bentz, S. (1995). Updated checklist of elm (Ulmus) cultivars for use in North America. ''Journal of Arboriculture'', 21:3 (May 1995), 121–131. International Society of Arboriculture, Champaign, Illinois, US

/ref>Smalley, E. B. & Lester, D. T. (1983), ''HortScience'' 18: 960–961, 1983. The foliage is distinctively sparse, allowing dappled sunlight beneath the canop

The leaves are narrowly leaf shape, elliptical, 5 cm to 10 cm in length, fern green when young, changing to a glossy, trichome-free, dusky spinach green. The perfect, wind-pollinated

apetalous Petals are modified leaves that surround the reproductive parts of flowers. They are often brightly colored or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''corolla''. Petals are usually ...

flowers emerge in early March. File:Ulmus Regal leaves.jpg, 'Regal' leaves File:Ulmus 'Regal'. The Meadows, Edinburgh.jpg, 'Regal' foliage File:Ulmus 'Regal'. Craigleith Road, Edinburgh (2).jpg, 'Regal' bole

Pests and diseases

'Regal' has a good resistance, rated 4 out of 5,Heybroek, H. M., Goudzwaard, L, Kaljee, H. (2009). ''Iep of olm, karakterboom van de Lage Landen'' (:Elm, a tree with character of the Low Countries). KNNV, Uitgeverij. 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 ...

and

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. tricorp ...

, but is very susceptible to the 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 ...

'' in the United States. The tree's foliage was adjudged 'resistant' to Black Spot by the Plant Diagnostic Clinic of the

University of Missouri The University of Missouri (Mizzou, MU, or Missouri) is a public land-grant research university in Columbia, Missouri. It is Missouri's largest university and the flagship of the four-campus University of Missouri System. MU was founded in ...

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Cultivation

The tree performed particularly well in the Northern Arizona University trial

where, along with Ulmus 'Frontier', 'Frontier', it proved very tolerant of the hot and arid conditions in the eastern part of

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

, exhibiting minimal leaf scorch. In Europe, 'Regal' was introduced by the now-defunct Conrad-Appel nursery in Darmstadt and grown under licence by several Dutch and German nurseries as one of the serie

It has enjoyed modest success in Germany as a street tre

but remains uncommon in the UK, where it was introduced by the Conservation Foundation, UK, Conservation Foundation and marketed for a few years by Crowder's Nursery, near Lincoln. 'Regal' was planted in the

Royal Horticultural Society The Royal Horticultural Society (RHS), founded in 1804 as the Horticultural Society of London, is the UK's leading gardening charity. The RHS promotes horticulture through its five gardens at Wisley (Surrey), Hyde Hall (Essex), Harlow Carr (Nor ...

's garden at Harlow Carr,

North Yorkshire North Yorkshire is the largest ceremonial counties of England, ceremonial county (lieutenancy area) in England, covering an area of . Around 40% of the county is covered by National parks of the United Kingdom, national parks, including most of ...

. It was trialled by Edinburgh Council, and many healthy specimens survive in the city.'Regal' in Edinburgh: nomorepencils.com/dutch-elm-disease-in-edinburgh/; fombl.org.uk/nl4.pdf; fombl.org.uk/nl5.pdf 'Regal' also featured in trials in New Zealand during the 1990s at the Hortresearch station,

Palmerston North Palmerston North (; mi, Te Papa-i-Oea, known colloquially as Palmy) is a city in the North Island of New Zealand and the seat of the Manawatū-Whanganui region. Located in the eastern Manawatu Plains, the city is near the north bank of the ...

. File:Ulmus 'Regal'. Craigleith Road, Edinburgh (1).jpg, 'Regal', Craigleith Rd, Edinburgh File:Ulmus 'Regal' Germany.jpg, 'Regal' along a German highway File:cathedral - regal - pioneer - urban - laevis - den haag.jpg, Elm cultivars, Nether-lands; 'Regal' 2nd from left File:Regal elm in Hove.JPG, 'Regal' in Daleview Gardens,

Hove Hove is a seaside resort and one of the two main parts of the city of Brighton and Hove, along with Brighton in East Sussex, England. Originally a "small but ancient fishing village" surrounded by open farmland, it grew rapidly in the 19th c ...

(2008)

Notable trees

The UK TROBI champion is at Abbey Park, Leicester, measuring 14 m high, 26 cm

d.b.h. Diameter at breast height, or DBH, is a standard method of expressing the diameter of the trunk or bole of a standing tree. DBH is one of the most common dendrometric measurements. Tree trunks are measured at the height of an adult's breast, ...

in 2004.

Hybrid cultivars

* 'Repura', 'Revera'

Accessions

North America

Chicago Botanic Garden The Chicago Botanic Garden is a living plant museum situated on nine islands in the Cook County Forest Preserves. It features 27 display gardens in four natural habitats: McDonald Woods, Dixon Prairie, Skokie River Corridor, and Lakes and Shor ...

, US. 3 trees, no other details available. *

Holden Arboretum The Holden Arboretum, in Kirtland, Ohio, is one of the largest arboreta and botanical gardens in the United States, with more than , including devoted to collections and gardens. Diverse natural areas and ecologically sensitive habitats make up t ...

, US. Acc. no. 85–189

Europe

Brighton & Hove Brighton and Hove () is a city and unitary authority in East Sussex, England. It consists primarily of the settlements of Brighton and Hove, alongside neighbouring villages. Often referred to synonymously as Brighton, the City of Brighton and ...

City Council, UK.

NCCPG Plant Heritage, formerly known as the National Council for the Conservation of Plants and Gardens (NCCPG), is a botanical conservation organisation in the United Kingdom and a registered charity. It was founded in 1978 to combine the talents of b ...

Elm Collection. Some very big trees in Hangleton, Hove. *

Cambridge Botanic Garden The Cambridge University Botanic Garden is a botanical garden located in Cambridge, England, associated with the university Department of Plant Sciences (formerly Botany School). It lies between Trumpington Road to the west, Bateman Street to ...

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UK. No accession details available. *

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.Ostler, J. (2009) ...

Lincolnshire Lincolnshire (abbreviated Lincs.) is a Counties of England, county in the East Midlands of England, with a long coastline on the North Sea to the east. It borders Norfolk to the south-east, Cambridgeshire to the south, Rutland to the south-we ...

, UK. * Rombergparkbr>
Dortmund, Germany. Details not known. *

Harlow Carr Arboretu

Harrogate Harrogate ( ) is a spa town and the administrative centre of the Borough of Harrogate in North Yorkshire, England. Historically in the West Riding of Yorkshire, the town is a tourist destination and its visitor attractions include its spa w ...

, UK. Planted 1988. *Wijdemeren City Council, Netherlands. Elm collection. Planted in 2015 in Nederhorst den Berg (Randweg, Vincent van Goghstraat, Pieter de Hooghweg).

Nurseries

;North America *Johnson's Nurser

Menomonee Falls, Wisconsin Menomonee Falls is a village in Waukesha County, Wisconsin, United States, and is part of the Greater Milwaukee area. The population was 35,626 at the 2010 census, making it the most populous village in Wisconsin. It is the fourth largest commun ...

, US. *Klyn Nurserie

Perry, Ohio Perry is a village in Lake County, Ohio, United States. The population was 1,663 at the 2010 census. History It is named in honor of Commodore Oliver Hazard Perry to commemorate his victory over the British fleet at the Battle of Lake Erie in ...

, US. *Lake County Nurser

Perry, Ohio, US. *Sun Valley Garden Centr

Eden Prairie Eden Prairie is a city southwest of downtown Minneapolis in Hennepin County and the 16th-largest city in the State of Minnesota, United States. As of the 2020 census, it has a population of 64,198. The city is adjacent to the north bank of th ...

Minnesota Minnesota () is a state in the upper midwestern region of the United States. It is the 12th largest U.S. state in area and the 22nd most populous, with over 5.75 million residents. Minnesota is home to western prairies, now given over to ...

, US. ;Europe *Eisele GmbH & Co KG, Darmstadt, Germany. *Noordplan

Glimmen Glimmen is a village in the northeastern Netherlands. It is located in the municipality of Groningen, about 10 kilometres from the city. It had a population of around 1,342 in 2021. The river Drentsche Aa flows past the village, nearby the ''Huis ...

, Netherlands. *Pan-Global Plant

Frampton-on-Severn Frampton on Severn is a village and civil parish in Gloucestershire, England. The population is 1,432. Geography The village is approximately south of Gloucester, at . It lies on the east bank of the River Severn, and on the west bank of the ...

Gloucestershire Gloucestershire ( abbreviated Glos) is a county in South West England. The county comprises part of the Cotswold Hills, part of the flat fertile valley of the River Severn and the entire Forest of Dean. The county town is the city of Gl ...

, UK.

References

External links

*http://www.extension.iastate.edu/Publications/SUL4.pdf Summary, inc. photographs, of elm cultivars resistant to Dutch elm disease available in the United States. *http://fletcher.ces.state.nc.us/programs/nursery/metria/metria11/warren/elm.htm Warren, K., J. Frank Schmidt & Son Co. (2002). ''The Status of Elms in the Nursery Industry in 2000''. {{Elm species, varieties, hybrids, hybrid cultivars and species cultivars , state=collapsed Hybrid elm cultivar Ulmus articles with images Ulmus