“Ulmus davidiana var. japonica”的意思、由来-开放百科全书

The size and shape of the Japanese elm is extremely variable, ranging from short and bearing a densely branched broad crown similar to the Wych elm^[2] to tall, single-stemmed, with narrow crown similar to the English elm.^[3]^[4] Augustine Henry described one of the latter outside Iwamigawa, Hokkaido, railway station as being 34 m tall, with a clean stem to a height of approximately 15 m.^[5] Japanese elm is distinguished by the fawn colour of shoots at the end of their first season, the shoots often being roughened by minute tubercles or 'warts'.^[6]^[7]^[8] The young shoots often bear corky wings, similar to those of the European field elm U. minor, to which it is closely related. The leaves are generally obovate, < 11 cm long, and with a coarse upper surface.^[9] Like many of the European field elms, var. japonica retains its green foliage well into the autumn, before a late display of deep yellow. Bean noted that the variety from western China, formerly known as U. wilsoniana, has 16 to 22 pairs of leaf-veins, while the eastern type tree has not more than 16.^[10] The perfect, apetalous wind-pollinated flowers emerge in early spring, before the leaves. The samara, <15 mm long, is obovate to orbicular, occasionally hairy over its entire surface but more often glabrous,^[4]^[11] the seed touching the notch, the inner margins of which are ciliate, the stigmas being slightly incurved.^[12] Trees grown from seed at Great Fontley in southern England first flowered aged 13 years.^[13]

Pests and diseases

Natural populations of Japanese elm have a low to moderate resistance to Dutch elm disease. In trials in the Netherlands, susceptibility to disease was found to be commensurate with rate of growth, the more vigorous specimens exhibiting far more foliar damage after inoculation with the causal fungus.^[15] Careful selection in North America has produced a number of cultivars highly resistant to disease (see Hybrids, hybrid cultivars and cultivars below). The tree is resistant to the elm leaf beetle Xanthogaleruca luteola ^[14] but is moderately susceptible to elm yellows.^[15]

Cultivation

Japanese elm has been widely planted in northern Japan as a street tree. It was introduced to North America in 1895 as seed sent from Sapporo to the Arnold Arboretum, Massachusetts, whence two seedlings were donated to Kew Gardens, London, in 1897.^[16] The Späth nursery, Berlin, marketed Japanese elm in Europe from 1900,^[17] Kew obtaining a third specimen from them in that year.^[18] Specimens were supplied by Späth to the Royal Botanic Garden Edinburgh in 1903 as U. campestris japonica and may survive in Edinburgh, as it was the practice of the Garden to distribute trees about the city.^[19] Mature specimens of Japanese elm (the largest with a bole-girth 2.9 m) stand on Leith Links (2018), near the former Leith Academy buildings.^[20] A specimen of U. campestris japonica obtained from Späth stood in the Ryston Hall arboretum, Norfolk,^[21] in the early 20th century.^[22] The Arnold Arboretum specimens grew rapidly, and first flowered aged 12 years. A form from western China, for many years distinguished as U. wilsoniana Schneider, was introduced to the Arnold Arboretum in 1910. Unlike many Asiatic species, Japanese elm is tolerant of a mild, maritime climate with heavy winter rainfall and was consequently considered of potential use in the Dutch elm breeding programme led by H. M. Heybroek at the Dorschkamp Research Institute at Wageningen.^[23] In 1977, Heybroek collected the tree in Japan, with the result that there is now a small forest of Japanese elm in southern Flevoland, the largest plantation of the species beyond its native land.^[24]

Specimens planted at the Sir Harold Hillier Gardens in Hampshire, England, in 1977 have grown very well on heavy clay in an open location, where they support colonies of the White-letter Hairstreak Satyrium w-album. In trials elsewhere in Hampshire conducted by Butterfly Conservation, the tree also proved tolerant of dry soils on chalk and soils waterlogged in winter, although growth has been comparatively slow.^[13] The species is not known to sucker from roots.^[4]

Leaves from the tree were eaten during the Great Chinese Famine, but found to cause facial swelling.^[25]

Notable trees

In the UK, the TROBI Champion grows at the Royal Horticultural Society's Rosemoor garden in Devon, measuring 16 m tall in 2017. Another large tree grows at the Sir Harold Hillier Gardens, Romsey, measuring 13 m tall by 42 cm d.b.h. in 2003. A large specimen grows at Sussex University, Falmer, Brighton, but may be the cultivar 'Jacan'.^[27] The oldest specimen in Edinburgh had a bole-girth of 3.5 m (felled 2018).^[28]

Cultivars

Japanese elm was assessed in Canada as a substitute for native elms which had succumbed to Dutch elm disease. Six particularly hardy cultivars were released there in the 1980s; three were also raised in the United States [https://web.archive.org/web/20030413074605/http://fletcher.ces.state.nc.us/programs/nursery/metria/metria11/warren/elm.htm]: 'Discovery', 'JFS-Bieberich' = {{tdes|Emerald Sunshine|caps}} (formerly treated under U. propinqua Koidz.),

'Freedom', 'Jacan', 'Mitsui Centennial', 'Prospector' (formerly treated under Wilson's elm U. wilsoniana C.K. Schneid.), 'Reseda', 'Thomson', Validation^[29] However, most of the Canadian clones have now been withdrawn from commerce owing to the Canadian government's restrictions on the movement of elm within the country, adopted to prevent the spread of Dutch elm disease.

Hybrids and hybrid cultivars

The Japanese elm was widely used in the USA in hybridization experiments at the Morton Arboretum and University of Wisconsin,^[31]^[32] resulting in the release of the following cultivars: 'Cathedral', 'Morton' = {{tdes|Accolade|caps}}, 'Morton Glossy' = {{tdes|Triumph|caps}}, 'Morton Plainsman' = {{tdes|Vanguard|caps}}, 'Morton Red Tip' = {{tdes|Danada Charm|caps}}, 'Morton Stalwart' = {{tdes|Commendation|caps}}, 'New Horizon', 'Patriot', 'Rebona', 'Repura', 'Revera', and 'Sapporo Autumn Gold'.

The species has also been crossed with Dutch hybrids by the Istituto per la Protezione delle Piante (IPP) in Florence, Italy. Two clones, 'FL 610' and 'FL 626' are currently (2015) under evaluation in England by Butterfly Conservation.^[13]

Accessions

Nurseries

References

1. ^Makita, H., Miyagi, T., Miura, O., and Kikuchi, T. (1979). A study of an alder forest and an elm forest with special reference to their geomorphological conditions in a small tributary basin. In: Vegetation und Lansdschaft Japans. Bull: Yokohama Phytosoc. Soc. Japan 16, 1979
2. ^{{cite web|last=T. H.|first=Everett| year=1969|title=Living trees of the world|url=http://forestry.oxfordjournals.org/content/43/1/99.1.full.pdf|publisher= Thames and Hudson}}
3. ^{{cite web|first=Makins|last=F. K.|year=1967|url=http://www.worldcat.org/title/identification-of-trees-shrubs/oclc/500545778?ht=edition&referer=di|title=The Identification of Trees & Shrubs|publisher=Dent}}
4. ^¹²{{cite journal | last = Heybroek | first=Hans M.|journal = Proceedings of the Dutch Elm Disease symposium and workshop, October 5–9, Winnipeg, Manitoba|title = The Japanese elm species and their value for the Dutch elm breeding program|pages = 78–90|date=1981|url=http://krishikosh.egranth.ac.in/bitstream/1/2055474/1/MPKV-1936.pdf}}
5. ^Elwes, H. J. & Henry, A. (1913). The Trees of Great Britain & Ireland. Vol. VII. 1848–1929. Republished 2014 Cambridge University Press, {{ISBN|9781108069380}}
6. ^Elwes and Henry (1913), p.1923
7. ^Bean, W. J. (1988) Trees and shrubs hardy in Great Britain, 8th edition, Murray, London
8. ^Krüssman, Gerd, Manual of Cultivated Broad-Leaved Trees & Shrubs (1984 vol. 3)
9. ^ Hishiyama, C. (Ed.). (2018). A picture book of (Japanese) trees, p.79. (in Japanese). Seibidoshuppan, Japan. {{ISBN|9784415310183}}
10. ^Bean, W. J., 1988
11. ^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, USA
12. ^Bean (1988), Krüssman (1983)
13. ^¹²Brookes, A. H. (2017). Great Fontley Elm Trial, 2017 Report. Butterfly Conservation, Lulworth, England.
14. ^{{Cite web|url=http://www.sunshinenursery.com/survey.htm|access-date=17 July 2017|archiveurl=https://web.archive.org/web/20110719132152/http://www.sunshinenursery.com/survey.htm|title=Elm Leaf Beetle Survey|archive-date=2011-07-19}}
15. ^{{cite journal|last1=Mittempergher|first1=L|last2=Santini|first2=A|journal=Investigacion agraria: Sistemas y recursos forestales|title=The history of elm breeding|volume=13|issue=1|pages=161–177|date=2004|url=http://www.inia.es/gcontrec/Pub/161-177-(14)-The_history_1161943529015.pdf}}
16. ^{{cite web|first=Bean|last=W. J.|year=1981|url=https://www.amazon.com/Trees-shrubs-hardy-British-Isles/dp/117278583X|title=Trees and shrubs hardy in Great Britain, 7th edition|publisher=Murray, London}}
17. ^Späth Catalogue No.106, p.124 (1900-1901)
18. ^Elwes and Henry (1913), p.1924
19. ^RBGE Cultivated Herbarium Accessions Book: Oct. 1958 notes by Ronald Melville on specimen C2698
20. ^Identification by RBGE (email correspondence).
21. ^rystonhall.co.uk/
22. ^{{cite book| title=Ryston Hall Arboretum catalogue |date=c. 1920 |pages=13–14|url=https://commons.wikimedia.org/wiki/File:Ryston_Hall_Arboretum_Catalogue_c._1920_pages_13,14.jpg}}
23. ^¹{{cite journal |editor-first=D.A.|editor-last=Burdekin|journal = Forestry Commission Bulletin (Research on Dutch elm disease in Europe)|number=60|last=Heybroek|first= Hans M. |publisher=HMSO|location=London|date=1983|title=Resistant elms for Europe|pages=108–113|url=http://www.forestry.gov.uk/pdf/FCBU060.pdf/$FILE/FCBU060.pdf#page=118}}
24. ^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. {{ISBN|9789050112819}}. Photograph of Japanese elm in the Netherlands
25. ^Baranov, A .L. (1962). On the economic use of wild plants in N. E. China. Quarterly Journal of the Taiwan Museum, 15 (122), 1962, 107–115.
26. ^Labelled 'Forest Elms' by photographer (663highland) on Hokkaido University page
27. ^Johnson, O. (2011). Champion Trees of Britain & Ireland, p.168. Kew Publishing, Kew, London. {{ISBN|9781842464526}}.
28. ^Tree labelled Japanese elm by 'Friends of the Meadows and Bruntsfield Links', in Coronation Walk, The Meadows, Edinburgh: fombl.org.uk
29. ^{{cite journal|last1=Burdekin|first1=D.A.|last2=Rushforth|first2=K.D.|others=Revised by J.F. Webber|title=Elms resistant to Dutch elm disease|journal=Arboriculture Research Note|date=November 1996|volume=2/96|pages=1–9|url=https://www.trees.org.uk/kenticotrees/Trees.org.uk/files/90/90f2d2f6-3d77-459c-8288-d951b0bf9782.pdf|accessdate=26 October 2017|publisher=Arboricultural Advisory & Information Service|location=Alice Holt Lodge, Farnham|issn=1362-5128}}
30. ^Kim, M., & Lee, S. (1989). Korean J. Pl. Taxon. 19(1) (1989)
31. ^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
32. ^Smalley, E. B. & Guries, R. P. (1993). Breeding Elms for Resistance to Dutch Elm Disease. Annual Review of Phytopathology Vol. 31 : 325-354. Palo Alto, California
33. ^{{cite web|title=List of plants in the {elm} collection|publisher=Brighton & Hove City Council|access-date=23 September 2016|url=http://www.brighton-hove.gov.uk/content/leisure-and-libraries/parks-and-green-spaces/list-plants-collection}}
34. ^Royal Botanic Garden Edinburgh. (2017). List of Living Accessions: Ulmus

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