''Ulmus'' × ''hollandica'' 'Superba'

Ulmus × hollandica 'Superba'
'Superba', Magdeburg, 1907 (described here by its synonym, Ulmus praestans E. Schoch)
Hybrid parentage U. glabra × U. minor
Cultivar 'Superba'
Origin Europe

The hybrid elm cultivar Ulmus × hollandica 'Superba' is one of a number of intermediate forms arising from the crossing of the Wych Elm U. glabra with a variety of Field Elm U. minor. Boulger tentatively (1881)[1] and Green more confidently (1964)[2] equated it with a hybrid elm cultivated in the UK by Masters at Canterbury in the early 19th century, known as "Masters' Canterbury Seedling" or simply the Canterbury Elm. Loudon examined a specimen sent by Masters and considered it a hybrid,[3] calling it U. montana glabra major (not to be confused with U. major Smith, U. × hollandica 'Major').[4][5]

Green (1964) also equated Masters' Canterbury Elm with Osborne's U. montana superba with unusually large leaves, described in 1848 by Morren,[6] though Loudon had made no reference to large leaves.[2] Rehder (1915 & 1949) did not include this identification in his list of synonyms.[7][8]

An U. praestans E. Schoch, cultivated in Europe in the late 19th century and said by Krüssmann (1984) to have originated in Belgium, was equated by him with U. × hollandica 'Superba'.[9] A 1907 photograph shows an avenue of elms in Magdeburg, Germany, described as U. praestans E. Schoch, a "hybrid between U. scabra [U. glabra] and U. campestris [U. minor]" – i.e. as a form of U. × hollandica.[10] A 'Superba' was reputed by Louis Späth to have been "much esteemed as a street tree in Magdeburg" – presumably the clone in the photograph.[11] This suggests that Späth regarded U. praestans as synonymous with 'Superba'. A 'Superba' had appeared in Späth's catalogues from 1885,[11] from descriptions[12] probably the large-leaved U. montana superba of Morren, not U. praestans. Späth's catalogue of 1911–12 erroneously claimed that U. praestans E. Schoch was synonymous with Morren's U. montana superba.[13] Hartwig, who received specimens of U. praestans from Kiessling of the Magdeburg city nursery in 1908, said (1912) that "Ulmus montana superba, supposedly the same [as U. praestans], looks quite different when young, being wide with large, broad, dull green leaves, whereas U. praestans and U. glabra fastigiata show an elongated medium-sized shiny green leaf and densely pyramidal crown". He concluded that U. praestans was not Ulmus montana superba, but was indistinguishable in leaf or habit from U. glabra fastigiata Kirchner.[14] Späth admitted the error in an article in Möller's Deutsche Gärtner-Zeitung (1912),[15] confirming that U. praestans E. Schoch was a U. × hollandica hybrid, and implying that Morren's tree was a form of U. montana (Wych Elm). He corrected the error in his later catalogues, distinguishing between Morren's Ulmus montana superba and U. praestans E. Schoch (for which he adopted Henry's synonym Ulmus superba Henry), and marketing both cultivars in the interwar period.[16][11] U. superba Henry was a 'Superba' from Späth himself, planted at Kew in 1900, which Henry had described in 1913.[11] This confirms that Späth had also been marketing U. praestans as 'Superba' in the late 19th century. An undated herbarium specimen from Haarlem showing a hybrid cultivar labelled "U. × hollandica 'Superba' Rehd., received as U. praestans from Späth, Berlin" (see 'External links') matches Henry's description of Späth's tree planted in 1900 at Kew.

Any link between Canterbury Elm, Loudon's U. montana glabra major, in cultivation in England throughout the 19th century (see below), and U. praestans E. Schoch, in cultivation in Europe in the late 19th century, is unknown, but Loudon's description of a fast-growing hybrid like Huntingdon Elm, holding its leaves late, matches descriptions of U. praestans.

'Superba' was confirmed by Krüssmann in 1962 as a cultivar.[17][2]

Description

Descriptions of 'Superba' vary, as do herbarium specimens, confirming that more than one clone has been given the name.

Loudon described Ulmus montana glabra major, 'Canterbury Seedling', as a hybrid similar to Huntingdon Elm in bark and vigour, but more spreading in form, and holding its leaves late.[4]

Henry's description (1913) of Ulmus superba Henry is based on a tree at Kew from Späth, planted in 1900. Recognizing this clone as a hybrid, Henry listed it among what are now called U. × hollandica cultivars, as a rapidly growing, narrow, pyramidal tree with smooth bark and steeply ascending branches. It bore large smooth biserrate dark green leaves, 8–12 cm (3–4 in) long and 4–6 cm broad, very oblique at the base and similar to those of the Wych Elm, but with petioles 5–10 mm long. The flowers too resemble those of the Wych Elm. Henry noted that a tree grown at Kew labelled U. montana macrophylla fastigiata was "similar in all respects" to Späth's 1900 'Superba'.[11]

Späth (1930) described the U. × hollandica hybrid U. praestans Schoch, which he said was synonymous with the U. superba Henry that he himself had supplied to Kew, as "a vigorous tree with upswept branches and large dark green foliage, lasting long into the autumn".[16] Krüssman (1984), though he erroneously listed Morren's 'Superba' as a synonym, described U. × hollandica 'Superba' / U. praestans Schoch as a hybrid with leaves 8–12 cm with 15–18 pairs of veins (he includes a leaf-drawing), retained late into autumn, and an elliptic samarae 1.5–2 cm long with the seed nearly central.[9]

According to Fontaine (1968), the leaves of U. × hollandica 'Superba' are smaller than those of Huntingdon Elm, U. × hollandica 'Vegeta', and a lighter green, with yellow veins.[18] From his reference to Schleswig, where it was cultivated (see below), Fontaine may have been describing U. praestans Schoch.

Berndt (1915) reported that "U. montana superba, a tree known in the Magdeburg region as Ulmus praestans", was "easy to confuse with" the similarly fastigiate but less vigorous U. glabra fastigiata. The leaves of the former are "less broad and slightly lighter in colour, smoother, finer and more evenly veined".[19]

Pests and diseases

No cultivar called 'Superba' is noted to have any resistance to Dutch elm disease.

Cultivation

An "Ulmus montana glabra major, the Canterbury Seedling", was described at the Royal Victoria Park, Bath (Royal Avenue), in 1857[5] and 1902.[20]

Given Späth's naming error, it is not certain that one planting of U. montana superba at the Dominion Arboretum, Ottawa, Canada, in 1896 (probably sourced from Späth),[21] was U. × hollandica 'Superba' rather than Osborne and Morren's clone. Herbarium specimens show that three hybrid U. montana superba were sent by Späth to the Royal Botanic Garden Edinburgh in 1902;[22] these may survive in Edinburgh, as it was the practice of the Garden to distribute trees about the city (viz. the Wentworth Elm); the current list of Living Accessions held in the Garden per se does not list the plant.[23]

A 'Superba' from the Späth nursery in Berlin was reintroduced to the UK at Kew Gardens in 1900. It remains represented by a specimen at Wakehurst Place donated in 1949; it survives by being treated as a hedging plant, too low to attract the attentions of the Scolytus beetles which act as vectors of Dutch elm disease. Henry noted that a tree grown at Kew labelled U. montana macrophylla fastigiata was similar in all respects to Späth's 'Superba',[11]

As well as the Magdeburg plantings and the post-war Späth distribution noted above, the Hesse Nursery of Weener, Germany, supplied U. praestans Schoch in the 1930s.[24] Heybroek reported (1963) that 'Praestans' was regularly planted in Schleswig.[25]

'Belgium Elm' at Rochester, NY, c.1900

An elm described as 'Superba' obtained from Louis van Houtte in Belgium before 1841,[26] and so pre-dating the introduction of Osborne's 'Superba' to Belgium by Morren,[6] was photographed at the Ellwanger and Barry nursery at Mount Hope, Rochester, New York, c. 1900. However, the photograph is also captioned 'Belgium Elm'.[26] By 1915 this tree was considered "probably only a varietal form of U. glabra or another hybrid of that species".[27]

Herbarium specimens of hybrid 'Superba' vary, suggesting that, in addition to Morren's U. montana superba, more than one U. × hollandica cultivar was given the name (see 'External links' below). A 'Superba' is not on any accessions list of identified surviving trees in the UK, save the specimen maintained as part of a low hedge at Wakehurst Place – possibly a cutting from the hybrid Ottawa 'Superba' from Späth planted in 1896,[28] rather than Morren's clone.[11]

Putative specimens in the UK

A few putative specimens stand in the UK. An old narrowly pyramidal U. × hollandica with steeply ascending branches, which stands in Regent Road Park, Edinburgh (2016), has leaves that appear to match the RBGE 1902 herbarium-specimen of U. montana superba (see 'External links' below).

A large hybrid elm in Stanmer Park Arboretum, Brighton, has 'Superba'-like steeply ascending branches, and leaves matching 'Superba' herbarium specimens.

Notable trees

Fifty-four U. × hollandica 'Superba' (clone uncertain) were planted in Dalgas Boulevard, Frederiksberg, Copenhagen, Denmark, in 1920.[29][note 1]

Synonymy

Accessions

Europe

Notes

  1. ↑ A 1920 photograph of a newly-planted avenue in Dalgas Boulevard may show the trees.

References

  1. ↑ Boulger, George Simonds (1881). McLaren, John, ed. "On British Elms". Transactions of the Royal Scottish Arboricultural Society. Edinburgh. 9: 39. Retrieved 18 October 2017.
  2. 1 2 3 4 5 Green, Peter Shaw (1964). "Registration of cultivar names in Ulmus". Arnoldia. Arnold Arboretum, Harvard University. 24 (6–8): 41–80. Retrieved 16 February 2017.
  3. ↑ Loudon, Arboretum et fruticetum Britannicum, 1838, p.1405
  4. 1 2 Loudon, John Claudius (1838). Arboretum et fruticetum Britannicum. 3. p. 1404.
  5. 1 2 Hanham, F. (1857). A Manual for the Park (Royal Victoria Park, Bath). Longman, London.
  6. 1 2 Morren, Charles (1848). "Notice sur l'Orme des montagnes". Journal D'Agriculture Pratique de Belgique. 1 (1): 411–414. Retrieved 2017-02-21.
  7. ↑ Rehder, Alfred (1915). "Neue order kritische Gehölze". Mitteilungen der Deutschen Dendrologischen Gesellschaft. 24: 215–219. Retrieved 18 October 2017.
  8. ↑ Rehder, Alfred. "Ulmaceae". Bibliography of cultivated trees and shrubs hardy in the cooler temperate regions of the Northern Hemisphere. Jamaica Plain, Massachusetts: The Arnold Arboretum of Harvard University. pp. 135–143. Retrieved 18 October 2017.
  9. 1 2 3 Krüssmann, Gerd (1984). Manual of Cultivated Broad-Leaved Trees & Shrubs. 3. p. 410.
  10. ↑ Heinricy, B (1908). "Baumpflanzungen in den städten". Die Gartenkunst. 10: 50. Retrieved 17 June 2016.
  11. 1 2 3 4 5 6 7 Elwes, Henry John; Henry, Augustine (1913). The Trees of Great Britain & Ireland. 7. pp. 1873–1874. Republished 2004 Cambridge University Press, ISBN 9781108069380
  12. ↑ Katalog (PDF). 108. Berlin, Germany: L. Späth Baumschulenweg. 1902–1903. pp. 132–133.
  13. ↑ Späth catalogue 1911/12, p.137
  14. ↑ Hartwig, Karl Gustav (1913). "Ulmus praestans". Mitteilungen der Deutschen Dendrologischen Gesellschaft. 22: 302.
  15. ↑ Spath, L (1912). "Ulmus praestans = U. montana superba". Möllers Deutsche Gärtner-Zeitung. 27 (15): 177. Retrieved 17 October 2017.
  16. 1 2 Späth, Ludwig (1930). Späth-Buch, 1720-1930. Berlin: Self published. pp. 311–313, 351–352.
  17. ↑ Krüssmann, Gerd (1962). Handbuch der Laubgehölze. 2. p. 537.
  18. ↑ F. J., Fontaine (1968). "Ulmus". Dendroflora. 5: 37–55. Retrieved 30 August 2017.
  19. ↑ Berndt, C. (1915). "Notizen über Ulmen". Mitteilungen der Deutschen Dendrologischen Gesellschaft. 24: 288. Retrieved 18 October 2017.
  20. ↑ Inman, T. Frederic (1905). "The Elm". Proceedings of the Bath Natural History and Antiquarian Field Club. 10: 37. Retrieved 19 August 2016.
  21. ↑ Catalogue of the trees and shrubs in the arboretum and botanic gardens at the central experimental farm (2 ed.). 1899. p. 75.
  22. ↑ Accessions book. Royal Botanic Garden Edinburgh. 1902. pp. 45, 47.
  23. ↑ "List of Living Accessions: Ulmus". Royal Botanic Garden Edinburgh. Retrieved 21 September 2016.
  24. ↑ Hesse, Hermann Albert (1932). Preis- und Sortenliste. pp. 96–97. Retrieved 18 January 2018.
  25. ↑ Heybroek, Hans M. (1963). Iepen in Sleeswijk. p. 176. Retrieved 30 August 2017.
  26. 1 2 Meeham, Joseph (1903). "Ulmus Campestris Superba". The Florists' Exchange. 15: 230.
  27. ↑ "European Elms" (PDF). Bulletin of Popular Information. Arnold Arboretum, Harvard University. 1 (14): 56. 23 July 1915. Retrieved 18 October 2016.
  28. ↑ "ePIC - Detailed results from Living collection for ulmus". epic.kew.org. Retrieved 2017-10-19.
  29. ↑ Christensen, Tove (1990). "Roadside Trees - Stories of destiny Frederiksberg Allé and Dalgas Boulevard" (PDF). Dansk Dendrologisk Årsskrift. 8: 19–23.
  30. ↑ Schoch, G. von (1900). "Baumpflanzungen in den städten". Die Gartenkunst. 2: 66. Retrieved 17 June 2016.
  31. ↑ Beterams, J (1911). "Nochmals die wertvollen Ulmen". Mitteilungen der Deutschen dendrologischen gesellschaft. 20: 249–250. Retrieved 17 June 2016.

Broad-leaved U. x hollandica 'Superba'

  • "Herbarium specimen - WAG.1847048". Botany catalogues. Naturalis Biodiversity Center. (no provenance)
  • "Herbarium specimen - E00824746". Herbarium Catalogue. Royal Botanic Garden Edinburgh. Sheet described as U. montana superba (Royal Botanic Garden Edinburgh specimen, 1902, from Späth)
  • "Herbarium specimen - E00824743". Herbarium Catalogue. Royal Botanic Garden Edinburgh. Sheet described as U. montana superba (Royal Botanic Garden Edinburgh specimen, 1902, from Späth)
  • "Herbarium specimen - E00824747". Herbarium Catalogue. Royal Botanic Garden Edinburgh. Sheet labelled U. montana f. superba (1903 specimen); long shoot
  • "Herbarium specimen - L.1582073". Botany catalogues. Naturalis Biodiversity Center. Sheet labelled U. montana f. superba (1903 specimen); includes short shoot
  • "Herbarium specimen - L.1587031". Botany catalogues. Naturalis Biodiversity Center. Sheet described as U. x hollandica Mill. var. 'Superba' Rehd. (Arnold Arboretum specimen, 1930)
  • "Herbarium specimen - WAG.1911555". Botany catalogues. Naturalis Biodiversity Center. Sheet described as U. x hollandica Mill. var. 'Superba' Rehd. (Weener specimen, 1954)
  • "Herbarium specimen - WAG.1847053". Botany catalogues. Naturalis Biodiversity Center. Sheet described as U. x hollandica Mill. var. 'Superba' Rehd. (Wageningen specimen, 1960)
  • "Herbarium specimen - WAG.1847056". Botany catalogues. Naturalis Biodiversity Center. Sheet described as U. x hollandica Mill. 'Superba' (Garfield Park, Washington, D.C., 1966)

Narrower-leaved U. x hollandica 'Superba' with samara, "received as U. praestans from Späth"

  • "Herbarium specimen - WAG.1847052". Botany catalogues. Naturalis Biodiversity Center. Sheet described as U. x hollandica Mill. var. 'Superba' Rehd.; synonym U. praestans var. Späth (Haarlem specimen)
  • "Herbarium specimen - WAG.1847051". Botany catalogues. Naturalis Biodiversity Center. Sheet described as Ulmus Superba Henry, synonym U. praestans Schoch
  • "Herbarium specimen - WAG.1847050". Botany catalogues. Naturalis Biodiversity Center. Sheet re-labelled Ulmus × hollandica Mill. 'Superba' Rehd.; Vondelpark, Amsterdam
  • "Herbarium specimen - L.1587091". Botany catalogues. Naturalis Biodiversity Center. Royal Botanic Garden Edinburgh C2710, specimen originally labelled U. glabra Mill. 'Superba'
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