Ulmus laciniata

Ulmus laciniata
Ulmus laciniata leaves
Scientific classification
Kingdom:	Plantae
Division:	Magnoliophyta
Class:	Magnoliopsida
Order:	Rosales
Family:	Ulmaceae
Genus:	Ulmus
Species:	U. laciniata
Binomial name
Ulmus laciniata (Trautv.) Mayr
Synonyms
Ulmus laciniata f. holophylla Nakai Ulmus major Hohen. var. heterophylla Maxim. Ulmus montana With. var. laciniata Trautv.

Ulmus laciniata (Trautv.) Mayr, known variously as the Manchurian, Cut-leaf, or Lobed, Elm, is a deciduous tree native to the humid ravine forests of Japan, Korea, northern China, eastern Siberia and Sakhalin, growing alongside Cerciphyllum japonicum, Aesculus turbinata, and Pterocarya rhoifolia ^[1][2][3], at elevations between 700 m and 2200 m, though sometimes lower in more northern latitudes, notably in Hokkaido, eastern Siberia and Sakhalin.

The tree is virtually identical to the Wych Elm Ulmus glabra, and was originally treated as such by Houtzagers and Augustine Henry, but later accorded species status of its own largely by virtue of the enormous disjunction in their respective areas; U. glabra extending across Europe as far as the Urals, several thousand kilometres from U. laciniata in the Far East.

Description

Ulmus laciniata is chiefly distinguished by its leaves, often regularly incised to form between three and seven apical lobes, giving rise to its common synonym, the Cut-leaf Elm [3]. The tree can reach a height of 27 m, although the trunk rarely exceeds 0.5 m d.b.h. The bark is dark, grey brown and exfoliates in flakes. The branchlets are unwinged. The laciniate leaves are usually obtriangular, < 18 cm in length. The perfect wind-pollinated apetalous flowers are produced on second-year shoots in April (March in England), followed by elliptic < 20 mm × 14 mm samarae in May ^[4][5][6].

Trees grown from seed commence flowering in their eighth year. The Dutch elm breeding programme revealed that the tree has a relatively high degree (39 % seed viability) of self-fertility ^[7].

Pests and diseases

Elm leaf beetles

Natural populations of U. laciniata have only a marginal resistance to Dutch elm disease, lower than that of the Japanese Elm ^[8]. Moreover, in trials in Italy and the USA [4], U. laciniata was severely damaged by elm leaf beetles Xanthogaleruca luteola, indeed in Italy chemical controls were necessary to ensure the tree's survival, unlike its compatriots U. parvifolia and U. davidiana var. japonica which survived unscathed. The species is also susceptible to Elm Yellows.^[9].

Cultivation

The species was introduced to the West in 1905, but remains uncommon in cultivation. A specimen at the Ryston Hall, Norfolk, arboretum, obtained from the Leon Chenault[5] nursery in Orléans^[10], was killed by the earlier strain of Dutch elm disease prevalent in the 1930s. The tree was comprehensively evaluated in the Netherlands in the 1950s as a potential source of anti-fungal genes for use in the Dutch elm hybridization programme, but was found intolerant of all but the most sheltered and humid conditions ^[8]. Trees planted at the Sir Harold Hillier Gardens (sole accession died 2007) and as part of Butterfly Conservation's elm trials at Great Fontley Farm, Fareham, England, have confirmed the Dutch assessment ^[11].

The species is very difficult to propagate from hardwood cuttings, even under mist, often rooting but failing to develop foliage. There are no known cultivars of this taxon, nor is it known to be in commerce beyond the USA.

Subspecies & varieties

A variety was recognized by Rehder: Ulmus laciniata var. nikkoensis - the Nikko Elm.

Hybrid cultivars

Several hybrid cultivars were raised as part of the Dutch elm breeding programme at Wageningen (Heybroek, 1993), crossing the species with hybrids of U. wallichiana and U. minor to produce Clone no. 560, which in turn was crossed with Clone 720 (itself a complex cross involving U. glabra, U. minor, U. wallichiana, and U. pumila) to produce Clone 1234. None of these clones has been commercially released.

Accessions

North America

• Arnold Arboretum. Acc. no. 17909 wild collected, 250-2001 wild collected in Korea.
• Denver Botanic Gardens. Neither acc. no. nor origin disclosed.
• Morton Arboretum. Acc. no. 50-95 wild collected, Liaoning Province, China.
• U S National Arboretum [6], Washington, D.C., USA. Acc. nos.76252, 68989.

Europe

• Grange Farm Arboretum, Sutton St. James, Spalding, Lincolnshire, UK. Grafted tree, acc. no. 701.
• Great Fontley Farm, Fareham, UK, Butterfly Conservation Elm Trials plantation, Platts M 10, (from seed collected Hokkaido University campus, Sapporo, Japan).
• Hortus Botanicus Nationalis, Salaspils, Latvia. Acc. no. 18132,3,4,5,8.
• Linnaean Gardens of Uppsala, Sweden. Acc. no. 2001-1660, obtained from South Korea.
• Oxford University Botanic Garden, Harcourt Arboretum, UK. Acc. no. 1981061.1, from seed obtained from the Moscow Botanical Garden [7] in 1981. 5 specimens, all @ 3 m tall (2008), in Bluebell Wood.
• Royal Botanic Garden Edinburgh, UK. Acc. nos. 20022150 (grown from seed, Lawyer Nursery, USA); 20030906 and 20030907, both wild collected in South Korea.
• Tallinn Botanic Garden, Estonia [8]. No accession details available.

Nurseries

North America

• Sunshine Nursery [9], Clinton, Oklahoma.

References

1. ^ Sasaki, Y. (1979) Der Verband Pterocaryon rhoifoliae in Japan. In: Vegetation und Landschaft Japans. Eds: Miyawaki, A., and Okuda, S. Bull. Yokohama Phytosoc. Soc. Japan. 16, 1979. pp. 213-226
2. ^ Ohwi, J. (1984). Flora of Japan. ISBN 978-0874747089
3. ^ Qian, H., Krestov, P., Fu, P.-Y., Wang, Q.-L., Song, J.-S. & Chourmouzis, C. Phytogeography of Northeast Asia. http://www.biosoil.ru/files/00000052.pdf
4. ^ 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. [1]
5. ^ Ware, G. (1995). Little-known elms from China: landscape tree possibilities. Journal of Arboriculture, (Nov. 1995). International Society of Arboriculture, Champaign, Illinois, USA. [2]
6. ^ White, J & More, D. (2003). Trees of Britain & Northern Europe. Cassell's, London
7. ^ Went, J. A. (1954). The Dutch elm disease - Summary of 15 years' hybridisation and selection work (1937-1952). European Journal of Plant Pathology, Vol 60, 2, March 1954.
8. ^ ^{a b} Heybroek, H. M. (1981). The Japanese elm species and their value for the Dutch elm breeding program. Proceedings of the Dutch Elm Disease symposium and workshop. October 5–9, 1981, Winnipeg, Manitoba. pp 78-90
9. ^ Mittempergher, L. & Santini, A. (2004) The history of elm breeding. Investigacion agraria: Sistemas y recursos forestales 13(1): 161-177 (2004)
10. ^ Ryston Hall Arboretum catalogue, circa 1920
11. ^ Brookes, A. H. (2006). An evaluation of disease-resistant hybrid and exotic elms as larval host plants for the White-letter Hairstreak butterfly Satyrium w-album, Part 1. Butterfly Conservation, Lulworth, UK