Ulmus × hollandica 'Groeneveld' explained

Ulmus × hollandica 'Groeneveld'
Hybrid:	U. × hollandica × U. minor
Cultivar:	'Groeneveld'
Origin:	Netherlands

The Dutch hybrid elm cultivar Ulmus × hollandica 'Groeneveld' was cloned in 1949 at the De Dorschkamp Institute, Wageningen, and released in 1963 in response to the earlier, less virulent form of Dutch elm disease that afflicted Europe shortly after the First World War.^{[1] [2]} The cultivar was derived from a crossing of Dutch clones '49',^[3] (originally believed to be an English Wych Elm Ulmus glabra but later identified as another example of Ulmus × hollandica) and '1', a Field Elm Ulmus minor found in central France and marketed by the Barbier nursery in Orléans.^[4]

Description

The tree is slow growing, and produces a dense, upswept growth which initially made it popular as a street tree in the Netherlands.^[5] The dark-green obovate leaves are < 9 cm long by 4 cm broad, arranged in clusters on short branchlets.^{[6] [7] [8]}

Pests and diseases

'Groeneveld' has good resistance to Coral-spot fungus Nectria cinnabarina, and Black Spot http://soilplantlab.missouri.edu/plant/diseases/resistant.htm.However, like all the other Dutch hybrids released before 1989, it proved to have only marginal resistance, rated 3 out of 5 ^[9] to the later, virulent form of Dutch elm disease and consequently planting is no longer recommended where the disease is prevalent.^[10]

Cultivation

'Groeneveld' was also introduced elsewhere in Europe, including Britain, in small numbers. The tree was briefly propagated and marketed in the UK by the Hillier & Sons nursery, Winchester, Hampshire from 1975 to 1977, during which time 29 were sold.^{[11] [12]} The tree was planted in trials http://www.netspace.net.au/~stephenf/Resistant_Elms.html in Canberra, Australia started in 1988, but has not shown promise in that environment so far; it has however proved popular in New Zealand. There are several specimens in American arboreta (see under Accessions).

Notable trees

The TROBI Champion tree in the UK is at Stanmer Park, near Brighton, East Sussex, measuring 18 m high by 53 cm d.b.h. in 2002^[13]

Etymology

'Groeneveld' translates as 'green field', and was named for the eponymous de Dorschkamp trial site at Wageningen.

Hybrid cultivars

• FL 522: derived from a crossing with the Chinese species Ulmus chenmoui by the Istituto per la Protezione delle Piante in Florence; it has not been released to commerce.

Accessions

North America

• Holden Arboretum, US. Acc. no. 70 - 127
• Morton Arboretum, US. Acc. no. 76 - 72, 29 - 2007 (graft).

Europe

• Brighton & Hove City Council, UK. NCCPG Elm Collection http://www.brighton-hove.gov.uk/content/leisure-and-libraries/parks-and-green-spaces/list-plants-collection, UK champion: Stanmer Park, 18 m high, 53 cm d.b.h. in 2002.^[14]
• Grange Farm Arboretum http://www.thegardeningwebsite.co.uk/grange-farm-plants-speciality-rare-trees-shrubs-i411.html, Sutton St. James, Spalding, Lincs., UK. Acc. no. 830.
• Royal Botanic Garden Wakehurst Place, UK. Acc. no. 1975 - 6125
• Sir Harold Hillier Gardens, Romsey, UK. Acc. no. 1977.6442
• Wijdemeren City Council Netherlands. Elm Arboretum; Zuidsingel circa 1985 and Strandje Wijde Blik 2019 Kortenhoef; ‘s-Gravelandsevaartweg, Loosdrecht: ten trees planted 2018. 9 trees planted 2018 Nedervecht, Nederhorst den Berg.

Nurseries

Europe

• Bellwood Trees, Meigle, Perthshire, Scotland, UK. http://www.bellwoodtrees.com/index.php
• De Reebock http://www.dereebock.be, Zwalm, Belgium.
• Noordplant http://www.noordplant.nl, Glimmen, Netherlands.
• Westerveld Boomkwekerij http://www.westerveldbv.nl/, Opheusden, Netherlands.

Oceania

• Productive Trees Ltd. http://www.productive-trees.co.nz, Paeroa, Waikato, New Zealand.

Notes and References

1. Burdekin. D.A.. Rushforth. K.D.. Revised by J.F. Webber. Elms resistant to Dutch elm disease. Arboriculture Research Note. November 1996. 2/96. 1–9. 26 October 2017. 1362-5128.
2. Santamour . Frank S. . Bentz . Susan E. . May 1995 . Updated Checklist of Elm (Ulmus) Cultivars for use in North America. Journal of Arboriculture . 21 . 3. 122–131 . 20 June 2016.
3. https://bioportal.naturalis.nl/nl/specimen/WAG.1846749 Trial elm 'Clone 49', WAG.1846749 bioportal.naturalis.nl
4. Heybroek. H.M.. Holmes. F.W.. De iep 'Groeneveld'. Plant Disease Reporter. 15 March 1964. 48. 3. 187–189. 26 October 2017. The Groeneveld elm.
5. White, J. & More, D. (2002). Trees of Britain & Northern Europe. Cassell's, London.
6. Sheet labelled 'Baarn, trial elm no.296', 1962 = 'Groeneveld' (Heybroek); Samarae specimen. Sheet labelled 'Baarn, trial elm no.296', 1962
7. http://www.noordplant.nl/beeldbank/ulmus-hollandica-groeneveld/ulmus-hollandica-groeneveld-amsterdam-voltaplein-110722c-866 noordplant.nl, 'Groeneveld' leaves, Amsterdam
8. Photographs of 'Groeneveld' elm http://www.ca.uky.edu/agcollege/plantpathology/vaillanc/for410/Dutch%20Elm%20Disease/BASIC/DED/CORE/00/00/F9.HTML and samarae http://www.florapictures.com/photodetail.php?dir=2&amp;photocount=3&amp;plants=ULHGROEN&amp;photoid=1002228900
9. 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.
10. Book: Heybroek. H.M.. Sticklen. Mariam B.. Sherald. James L.. Dutch Elm Disease Research. 1993. Springer-Verlag. New York, USA. 16–25. 26 October 2017. The Dutch Elm Breeding Program. https://books.google.com/books?id=avvxBwAAQBAJ&pg=PA16. 978-1-4615-6874-2.
11. Hillier & Sons (1977). Catalogue of Trees & Shrubs. Hillier, Ampfield, UK.
12. Hillier & Sons Sales inventory 1962 to 1977 (unpublished).
13. Johnson, O. (2011). Champion Trees of Britain & Ireland, 169. Kew Publishing, Kew, London. .
14. Johnson, O. (2003). Champion Trees of Britain & Ireland. Whittet Press,