Ulmus 'Densa' Explained

Ulmus 'Densa'
Cultivar:	'Densa'
Genus:	Ulmus
Origin:	C. Asia

The elm cultivar Ulmus Densa was described from specimens growing near Ashkabad as U. densa Litv. in Schedae ad Herbarium Florae Rossicae (1908).^[1] Litvinov, reporting it growing wild in the mountains of Turkestan, Ferghana, and Aksu, as well as in cultivation, considered it a species, a view upheld by the Soviet publications Trees and Shrubs in the USSR (1951)^[2] and Flora of Armenia (1962),^[3] and by some current plant lists.^{[4] [5] [6]} Other authorities take it to be a form of U minor, distinctive only in its dense crown and upright branching.^{[7] [8] [9]} The Moscow State University herbarium gives (2020) Ulmus minor as the "accepted name" of U. densa Litv..^{[10] [11]}

Litvinov considered U. minor 'Umbraculifera', with its "denser crown and more rounded form", a cultivar of U. densa,^[7] calling it U. densa var. bubyriana. Rehder (1949) and Green (1964), ignoring reports of the wild form, considered U. densa a synonym of 'Umbraculifera'.^{[12] [13]} The U. densa photographed by Meyer in Aksu, Chinese Turkestan on his 1911-12 expedition does not appear to be the tidy grafted cultivar 'Umbraculifera' and was said to be named 'Seda'.^{[14] [15]} Zielińksi in Flora Iranica (1979) considered 'Umbraculifera' an U. minor cultivar.^[16]

In its natural range U. densa overlaps with U. pumila. The extent of hybridization between the two is not known.

Description

Litvinov noted that the tree "differed little from U. glabra Mill." [:''U. minor'']^[17] except in its erect branches and dense oblong crown.^[18] The leaves were "generally smaller" ^[19] and the branches "smooth and lighter in colour". As with the hybrid U. × androssowii, its compact branch structure helps the tree conserve moisture.^[20]

Pests and diseases

Not known.

Cultivation

Litvinov said that U. densa was "widely cultivated" in gardens in Turkestan. It is one of a number of elms known locally as 'karagach' or 'karagatch' [:'black tree' = elm].^{[21] [22] [23]} In western Europe U. densa Litv. was distributed by Hesse's Nurseries, Weener, Germany, in the 1930s.^[24]

Notable trees

A large, well-grown specimen stands in Dushanbe Botanic Gardens, Tajikistan (2019).^{[25] [26]}

Cultivars

These include one of the oldest of elm cultivars, 'Umbraculifera', and a number of elms introduced to the West by the Späth nursery of Berlin.

• U. minor 'Umbraculifera', (?) U. minor 'Rueppellii', (?) U. 'Globosa', (?) U.' 'Koopmannii'

Meyer (1912) identified three cultivars of U. densa: 'Stamboul', 'Kitaisky' and 'Seda'.^{[27] [15]}

Hybrid cultivars

The tree, or its cultivar form 'Umbraculifera', has hybridised with U. pumila to produce U. × androssowii.

Accessions

None known.

External links

• efloras.org: U. densa Litv. illustrations (figures 10 to 14)
• Photographs labelled U. densa on Plant Photo Bank of China, ppbc.iplant

Notes and References

1. Schedae ad Herbarium Florae Rossicae, VI. 163-165 (1908)
2. Book: Sokolov, S. Ya. 1951 . 504–505 . Деревья и кустарники СССР. Trees & Shrubs in the USSR . ru. 2. Moscow.
3. Book: Takhtajan, Armen Leonovich. 1962 . 341–342 . Флора Армении. Flora of Armenia. ru. 4. Yerevan.
4. The Plant List: Ulmus densa Litv., accessdate: December 14, 2016
5. Tropicos: Name - Ulmus densa Litv., accessdate: December 14, 2016
6. Ulmus densa was one of two elm "species" determined by Litvinov; the second, his Ulmus celtidea, has not been accepted by other authorities (Journal of the Arnold Arboretum, vol.19, 1938; p.264).
7. Book: Elwes. Henry John. Henry John Elwes. Henry. Augustine. Augustine Henry. 1913. The Trees of Great Britain & Ireland. 7. 1893.
8. Book: De Langhe. Jan. Vegetative key to species European cultivation (Ulmaceae). 7 April 2016. Ghent University Botanical Garden. Ghent. 5. 18 December 2016.
9. Plantarium: Ulmus densa - Галерея субтаксонов - Плантариум (in Russian), accessdate: December 18, 2016
10. https://plant.depo.msu.ru/open/public/en/item/MW0591858 Moscow State University herbarium, Specimen MW0591858, plant.depo.msu.ru
11. https://plant.depo.msu.ru/open/public/en/item/MW0591857 Moscow State University herbarium, Specimen MW0591857, plant.depo.msu.ru
12. Web site: Bibliography of cultivated trees and shrubs hardy in the cooler temperate regions of the Northern Hemisphere . Alfred Rehder . 142 . Arnold Arboretum of Harvard University . 1949.
13. Green . Peter Shaw . Peter Shaw Green . 1964 . Registration of cultivar names in Ulmus. Arnoldia . 24. 41–80 . 6–8 . . 16 February 2017.
14. Meyer's photograph (5675) of Ulmus densa Turkestan. Aksu, Turkestan. February 1911
15. Meyer's photograph (5676) of Ulmus densa Turkestan. Aksu, Turkestan. February 1911
16. J. Zielińksi, 'Ulmaceae', Flora Iranica, ed. K. H. Rechinger (Graz, 1979)
17. https://plant.depo.msu.ru/open/public/en/item/MW0591858 Specimen MW0591858 "Moscow State University herbarium"
18. http://uses.plantnet-project.org/en/Ulmus_densa_(Gintzburger_et_al.,_2003)#/media/File:Ulmus_densa_1_Gintzburger_et_al.jpg Photograph captioned U. densa, uses.plantnet-project.org
19. Sheet labelled Ulmus densa Litv.; USSR, 1955; Sheet labelled Ulmus densa Litv.; specimen from Kazvin, Iran (1948); Sheet labelled Ulmus densa Litv.; specimen from Iraq (1957); Sheet labelled Ulmus densa Litv.; samara specimen from Isfahan, Iran (1948); (top left-hand specimen) Field elm leaves from Kurrum valley, Afghanistan (1879)
20. World Digital Library: Elm Trees. Samarkand, accessdate: December 18, 2016
21. Rickmers, W. Rickmer, The Duab of Turkestan, a physiographic sketch and account of some travels (Cambridge, 1913), p.172
22. https://archive.org/details/throughcentralas00lans/page/464/mode/2up Lansdell, Henry, Through Central Asia (London, 1887), p.464
23. https://archive.org/details/leturkestanrusse00voeiuoft/page/68/mode/2up Voeikov, Aleksandr Ivanovich, Le Turkestan Russe (Paris, 1914), p.68
24. Book: Hesse. Hermann Albert. Preis- und Sortenliste. 1932. 96–97. 18 January 2018.
25. http://www.plantarium.ru/page/image/id/164689.html U. minor / Ulmus densa Litv. www.plantarium.ru
26. Google Maps: Dushanbe Botanic Gardens - Google Maps (May 2019), accessdate: August 21, 2019
27. Meyer, F. N. (1912). Seeds and plants imported during the period from January 1 to March 31, 1912: Inventory No.30, Nos 32829 - 32831. Bureau of Plant Industry - Bulletin No. 282. Washington, Government Printing Office, 1913.