The
Japanese elm cultivar
A cultivar is a kind of Horticulture, cultivated plant that people have selected for desired phenotypic trait, traits and which retains those traits when Plant propagation, propagated. Methods used to propagate cultivars include division, root a ...
''Ulmus davidiana'' var. ''japonica'' 'Prospector' was originally treated as a cultivar of Wilson's elm ''U. wilsoniana''
Schneid., a species
sunk as ''Ulmus davidiana'' var. ''japonica'' by Fu.
[Fu, L., Xin, Y. & Whittemore, A. (2002). Ulmaceae, in Wu, Z. & Raven, P. (eds) ''Flora of China'', Vol. 5 (Ulmaceae through Basellaceae). Science Press, Beijing, and Missouri Botanical Garden Press, St. Louis, US]
/ref> A U.S. United States National Arboretum, National Arboretum introduction (NA 55398), it was selected in 1975 from a batch of 1965 seedlings in Delaware
Delaware ( ) is a U.S. state, state in the Mid-Atlantic (United States), Mid-Atlantic and South Atlantic states, South Atlantic regions of the United States. It borders Maryland to its south and west, Pennsylvania to its north, New Jersey ...
, Ohio
Ohio ( ) is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders Lake Erie to the north, Pennsylvania to the east, West Virginia to the southeast, Kentucky to the southwest, Indiana to the ...
, and released without patent restrictions in 1990.[''HortScience'', 26, 81-82, 1991.] 'Prospector' proved moderately successful in the US National Elm Trial, averaging a survival rate of 76% overall.
'Prospector' was introduced to the UK in 2009, by Hampshire & Isle of Wight Branch, ''Butterfly Conservation
Butterfly Conservation (BC) is a UK-wide nonprofit environmentalist organization and charity dedicated to conserving butterflies, moths, and the environment. The charity uses its research to provide advice on how to conserve and restore butterf ...
'', as part of an assessment of DED-resistant cultivars as potential hosts of the endangered White-letter Hairstreak
The white-letter hairstreak (''Satyrium w-album'') is a butterfly in the family Lycaenidae.
Appearance and behaviour
A dark little butterfly that spends the majority of its life in the tree tops, feeding on honeydew, making it best observed thr ...
.
Description
'Prospector' is a medium-size elm with a light-grey bark, attaining a height of approximately 14 m and developing a vase shape broadly similar to 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. The trees can live for several hundred years. It is a very hardy species that can ...
but with lower-drooping branche
The deep-green, glossy leaf shape, obovate leaves are < 11 cm long by 8 cm wide, emerging orange-red and turning yellow in autumn. The perfect
Perfect commonly refers to:
* Perfection; completeness, and excellence
* Perfect (grammar), a grammatical category in some languages
Perfect may also refer to:
Film and television
* ''Perfect'' (1985 film), a romantic drama
* ''Perfect'' (20 ...
, apetalous
Petals are modified leaves that form an inner whorl surrounding the reproductive parts of flowers. They are often brightly coloured or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''coroll ...
wind-pollinated flowers emerge in early spring, before the leaves. The samara
Samara, formerly known as Kuybyshev (1935–1991), is the largest city and administrative centre of Samara Oblast in Russia. The city is located at the confluence of the Volga and the Samara (Volga), Samara rivers, with a population of over 1.14 ...
, 20 mm long by 8–10 mm wide, is narrowly obovate, the seed between centre and notch. Specimens grown in Hampshire
Hampshire (, ; abbreviated to Hants.) is a Ceremonial counties of England, ceremonial county in South East England. It is bordered by Berkshire to the north, Surrey and West Sussex to the east, the Isle of Wight across the Solent to the south, ...
, England, first flowered and fruited aged 10 years. The tree was also the first to flower every year, usually by mid-January.[Brookes, A. H. (2022). ''Great Fontley Elm Trial, 2022 Report''. Butterfly Conservation, ]Lulworth
Lulworth is the popular name for an area on the coast of Dorset, South West England notable for its castle and cove. However, there is no actual place or feature called simply "Lulworth", the villages are East and West Lulworth and the coastal f ...
, England.
The tree grows at a comparatively modest pace in the United States; specimens planted at UC Davis
The University of California, Davis (UC Davis, UCD, or Davis) is a Public university, public Land-grant university, land-grant research university in Davis, California, United States. It is the northernmost of the ten campuses of the University ...
as part of the National Elm Trial
The National Elm Trial was an American volunteer effort to evaluate a range of newly developed elm cultivars as replacements for elms destroyed by Dutch elm disease. The Colorado State University College of Agricultural Sciences coordinated the ...
increased in height by 0.85 m and diameter at breast height
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, ...
by 2 cm in the first few years after establishment [McPherson, G. et al. (2008). National elm trial: Initial report from Northern California. ''Western Arborist'', Fall 2009, 32–36.]
The species does not sucker from roots.
Image: Ulmus 'Prospector' emergent leaf.jpg, 'Prospector' emergent leaf colouring.
File:Ulmus 'Prospector' samarae.jpg, 'Prospector' samarae with £1 coin as scale
File:Samara of Ulmus davidiana var. japonica 'Prospector'.jpg, 'Prospector' samara
Pests and diseases
'Prospector' has featured in several elm trials in the United States, notably those conducted by the Northern Arizona University
Northern Arizona University (NAU) is a public research university based in Flagstaff, Arizona, United States. Founded in 1899, it was the third and final university established in the Arizona Territory.
It is one of the three universities gove ...
at Holbrook, eastern Arizona
and Townsend & Douglass [Townsend A. M. & Douglass, L. W. ''Variation among American Elm Clones in Long-term Dieback, Survival, and Growth Response to Ophiostoma Inoculation''] which established that the tree's survival rate after inoculation with the Dutch elm disease pathogen was 100%. In trials in California, the tree exhibited a singular sensitivity to boron
Boron is a chemical element; it has symbol B and atomic number 5. In its crystalline form it is a brittle, dark, lustrous metalloid; in its amorphous form it is a brown powder. As the lightest element of the boron group it has three ...
concentrations of > 200 ppm in the soil, causing marginal necrosis
Necrosis () is a form of cell injury which results in the premature death of cells in living tissue by autolysis. The term "necrosis" came about in the mid-19th century and is commonly attributed to German pathologist Rudolf Virchow, who i ...
on the leaves.[Costello, L. R. (2004). A 10-year evaluation of the performance of four elm cultivars in California, U.S. ''Journal of Arboriculture'', March, 2004]
/ref> Moreover, although also highly resistant to 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 ...
'
(no damage whatsoever was recorded in the aforementioned trials at U C Davis ) 'Prospector' is a favoured food of leaf hoppers which can seriously disfigure foliage by midsummer, and is moderately susceptible to the Japanese Beetle
The Japanese beetle (''Popillia japonica'') is a species of Scarabaeidae, scarab beetle. Due to the presence of Predation, natural predators, the Japanese beetle is not considered a pest in its native Japan, but in North America and some region ...
.[Brady, C., Condra, J., & Potter, D. (2008) Resistance of Landscape-suitable Elm (Ulmus spp.) Cultivars to Japanese Beetle, Leaf Miners, and Gall Makers. ''2008 Research Report, Nursery & Landscape Program'', pp 15, 16. University of Kentucky.]
Tolerance of Elm Yellows in the United States was found to be poor. However, the disease has proved difficult to transmit experimentally to this cultivar, and there appear to be no natural infections.[Sinclair, W. A., Townsend, A. M., Griffiths, H. M., & Whitlow, T. H. (2000). Responses of six Eurasian Ulmus cultivars to a North American elm yellows phytoplasma. ''Plant disease'', Vol. 84, No.12, 1266–1270. American Phytopathological Society, St. Paul, MN]
Cultivation
'Prospector' performed well in California
California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...
, although it "needed substantial training in the first two to three years". In Arizona, the tree proved unsuited to the hot, arid climate and suffered > 50% leaf scorch. In trials conducted by the University of Minnesota
The University of Minnesota Twin Cities (historically known as University of Minnesota) is a public university, public Land-grant university, land-grant research university in the Minneapolis–Saint Paul, Twin Cities of Minneapolis and Saint ...
, 'Prospector' was appreciated for its extraordinary vigour but faulted for the weakness of its wood, notably stem breakage owing to bark inclusion.[Giblin, C. P. & Gillman, J. H. (2006). ''Elms for the Twin Cities: A Guide for Selection and Maintenance.'' University of Minnesota.] Nonetheless, it is considered by the U.S. Department of Agriculture
The United States Department of Agriculture (USDA) is an executive department of the United States federal government that aims to meet the needs of commercial farming and livestock food production, promotes agricultural trade and production ...
(USDA) as suitable for Zones
Zone, Zones or The Zone may refer to:
Places Military zones
* Zone, any of the divisions of France during the World War II German occupation
* Zone, any of the divisions of Germany during the post-World War II Allied occupation
* Korean Demilit ...
4–7. The tree is currently being evaluated in the National Elm Trial
The National Elm Trial was an American volunteer effort to evaluate a range of newly developed elm cultivars as replacements for elms destroyed by Dutch elm disease. The Colorado State University College of Agricultural Sciences coordinated the ...
br>
coordinated by Colorado State University
Colorado State University (Colorado State or CSU) is a Public university, public Land-grant university, land-grant research university in Fort Collins, Colorado, United States. It is the flagship university of the Colorado State University Syst ...
.
'Prospector' was introduced to Europe by ''Butterfly Conservation
Butterfly Conservation (BC) is a UK-wide nonprofit environmentalist organization and charity dedicated to conserving butterflies, moths, and the environment. The charity uses its research to provide advice on how to conserve and restore butterf ...
'' in 2009 as part of its elm trials programme in Hampshire
Hampshire (, ; abbreviated to Hants.) is a Ceremonial counties of England, ceremonial county in South East England. It is bordered by Berkshire to the north, Surrey and West Sussex to the east, the Isle of Wight across the Solent to the south, ...
but has exhibited very slow growth, its stem increasing by just 2 mm in diameter at breast height
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, ...
per annum.[
The tree was also included in trials in New Zealand undertaken by Hortresearch at ]Palmerston North
Palmerston North (; , colloquially known as Palmerston or Palmy) is a city in the North Island of New Zealand and the seat of the Manawatū-Whanganui region. Located in the eastern Manawatū Plains, the city is near the north bank of the Manaw ...
in the 1990s.
Synonymy
''Ulmus wilsoniana'' C. K. Schneid. 'Prospector'.
Hybrid cultivars
* 'Patriot'
Accessions
;North America
*Arnold Arboretum
The Arnold Arboretum is a botanical research institution and free public park affiliated with Harvard University and located in the Jamaica Plain and Roslindale, Massachusetts, Roslindale neighborhoods of Boston.
Established in 1872, it is the ...
, US. Acc. no. 134-2002
*Bartlett Tree Experts, North Carolina
North Carolina ( ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It is bordered by Virginia to the north, the Atlantic Ocean to the east, South Carolina to the south, Georgia (U.S. stat ...
, US. Acc. nos. 2001-261/2/3, 2001–488, 2001-490
*Brenton Arboretum
The Brenton Arboretum is a 141-acre arboretum and public garden in Dallas Center, Iowa, United States, established in 1997. The arboretum displays 175 native Iowa trees and shrubs suitable to the site, as well as many other tree species which c ...
, Dallas Center
Dallas Center is a city in Dallas County, Iowa, United States. The population was 1,901 during the 2020 census. It is part of the Des Moines– West Des Moines Metropolitan Statistical Area.
History
Dallas Center got its start in the year 186 ...
, Iowa
Iowa ( ) is a U.S. state, state in the upper Midwestern United States, Midwestern region of the United States. It borders the Mississippi River to the east and the Missouri River and Big Sioux River to the west; Wisconsin to the northeast, Ill ...
, US. 5 trees, acquired 2009. Acc. no. not known.
*Dominion Arboretum
The Dominion Arboretum () is an arboretum part of the Central Experimental Farm of Agriculture and Agri-Food Canada in Ottawa, Ontario, Canada. Originally begun in 1889, the Arboretum covers about of rolling land between Prince of Wales Drive, ...
, Ottawa, Ontario
Ottawa is the capital city of Canada. It is located in the southern Ontario, southern portion of the province of Ontario, at the confluence of the Ottawa River and the Rideau River. Ottawa borders Gatineau, Gatineau, Quebec, and forms the cor ...
, Canada, No acc. details.
*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 u ...
, US. Acc. no. 95-141
*Morton Arboretum
The Morton Arboretum, in Lisle, Illinois, United States, is a public garden and outdoor museum with a library, herbarium, and program in tree research including the Center for Tree Science. Its grounds, covering 1,700 acres (6.9 square kilometre ...
, US. Acc. no. 61–2003, 213-2012
* Parker Arboretum, Parker Parker may refer to:
People
* Parker (given name), including a list of people and fictional characters with the given name
* Parker (surname), including a list of people and fictional characters with the surname
Arts and entertainment
* ''Parke ...
, Colorado
Colorado is a U.S. state, state in the Western United States. It is one of the Mountain states, sharing the Four Corners region with Arizona, New Mexico, and Utah. It is also bordered by Wyoming to the north, Nebraska to the northeast, Kansas ...
, US. No acc. details
*Scott Arboretum
Scott Arboretum () is an arboretum coterminous with the campus of and operated by Swarthmore College. It is open to the public daily without charge. The arboretum was established and endowed by the Scott family in 1929 in honor of Arthur Hoyt Sc ...
, US. Acc. no. 91-241
*Smith College
Smith College is a Private university, private Liberal arts colleges in the United States, liberal arts Women's colleges in the United States, women's college in Northampton, Massachusetts, United States. It was chartered in 1871 by Sophia Smit ...
, US. Acc. nos. 13303, 502
*University of Idaho
The University of Idaho (U of I, or UIdaho) is a public land-grant research university in Moscow, Idaho, United States. Established in 1889 and opened three years later, it was the state's sole university for 71 years, until 1963.
The un ...
Arboretum, US. Three trees, Acc. nos. 1995011, 1995085
* U S National Arboretum, Washington, D.C.
Washington, D.C., formally the District of Columbia and commonly known as Washington or D.C., is the capital city and federal district of the United States. The city is on the Potomac River, across from Virginia, and shares land borders with ...
, US. Acc. no. not known.
;Europe
*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) ...
, Sutton St James
Sutton St James is a village and civil parish in the South Holland, Lincolnshire, South Holland district of Lincolnshire, England, about south-west of Long Sutton, Lincolnshire, Long Sutton.
Lying in the Lincolnshire Fens, Sutton St James did ...
, Spalding, Lincs., UK. Acc. no. 823.
*Great Fontley
Funtley – from the Anglo-Saxon, "Funtaleg", " spring field (clearing)", is a hamlet or exurb north of Fareham, Hampshire, England. It forms a projection towards the South Downs National Park and is generally included within Fareham's popul ...
, Fareham
Fareham ( ) is a market town at the north-west tip of Portsmouth Harbour, between the cities of Portsmouth and Southampton in south east Hampshire, England. It gives its name to the Borough of Fareham. It was historically an important manufac ...
, UK. ''Butterfly Conservation
Butterfly Conservation (BC) is a UK-wide nonprofit environmentalist organization and charity dedicated to conserving butterflies, moths, and the environment. The charity uses its research to provide advice on how to conserve and restore butterf ...
'' Elm trials plantation, Home Field, one 0.8 m whip planted 2009.
*Istituto per la Protezione delle Piante The Istituto per la Protezione delle Piante (IPP), or 'Institute of Plant Protection', is part of the Food Department of the Consiglio Nazionale delle Ricerche (CNR; "Italian National Research Council"), an Italian government organization with the ...
, Florence
Florence ( ; ) is the capital city of the Italy, Italian region of Tuscany. It is also the most populated city in Tuscany, with 362,353 inhabitants, and 989,460 in Metropolitan City of Florence, its metropolitan province as of 2025.
Florence ...
, Italy. 2 small plants, (2010).
*Royal Botanic Garden Edinburgh
The Royal Botanic Garden Edinburgh (RBGE) is a scientific centre for the study of plants, their diversity and conservation, as well as a popular tourist attraction. Founded in 1670 as a physic garden to grow medicinal plants, today it occupies ...
, UK. Acc. no. 20092086. Listed as ''U. japonica'' 'Prospector'.
*Sir Harold Hillier Gardens
The Sir Harold Hillier Gardens is an arboretum comprising 72 hectares (180 acres) accommodating over 42,000 trees and shrubs in about 12,000 taxa, notably a collection of oaks, camellia, magnolia and rhododendron.
The Gardens are located north ...
, Romsey
Romsey ( ) is a town in the Test Valley district of Hampshire, England. The town is situated northwest of Southampton, southwest of Winchester and southeast of Salisbury. It sits on the outskirts of the New Forest, just over northeast of ...
, Hampshire
Hampshire (, ; abbreviated to Hants.) is a Ceremonial counties of England, ceremonial county in South East England. It is bordered by Berkshire to the north, Surrey and West Sussex to the east, the Isle of Wight across the Solent to the south, ...
, UK. Acc. no. 2009.0454.
Nurseries
;North America
(Widely available)
;Europe
*Pan-global Plant
Frampton on Severn, Gloucestershire
Gloucestershire ( , ; abbreviated Glos.) is a Ceremonial counties of England, ceremonial county in South West England. It is bordered by Herefordshire to the north-west, Worcestershire to the north, Warwickshire to the north-east, Oxfordshire ...
, 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.
usda.gov
Prospector, USNA information sheet.
{{Elm species, varieties, hybrids, hybrid cultivars and species cultivars , state=collapsed
Japanese elm cultivar
Ulmus articles with images
Ulmus