Ulmus davidiana, also known as the David elm, or Father David elm (named after the botanist
Armand David, who collected specimens), is a small
deciduous tree widely distributed across China, Mongolia, Korea, Siberia, and Japan, where it is found in wetlands along streams at elevations of 2000–2300 m (6,500–7,500 ft).[2] The tree was first described in 1873 from the hills north of
Beijing, China.[3]
Classification
Two varieties of Ulmus davidiana are recognized:
var. davidiana, occurring only in China, and
var. japonica Rehder, the more widely ranging Japanese Elm.[2] Some authorities, however, do not consider japonica to be a variety of U. davidiana, The Illustrated Flora of the Primorsky Territory, Russian Far East (2019), for example, maintaining U. japonica as a species.[4][5] In 1916
Arnold Arboretum described the two as different species.[6]Harold Hillier originally (1973) listed and described japonica as a variety of U. davidiana,[7] but
Hillier's separated the two as distinct species in later editions of their Manual of Trees and Shrubs.[8]
Description
Ulmus davidiana is considered to have a remarkable resemblance to the
American elm (U. americana) in all but ultimate size.[9] The tree grows to a maximum height of 15 m (50 ft), with a relatively slender trunk < 0.3 m (1 ft)
d.b.h. supporting a dense canopy casting a heavy shade. Its bark remains smooth for a comparatively long time, before becoming longitudinally fissured. The leaves, often dark red on emergence, are
obovate to obovate-elliptic < 10 cm (4 in) × < 5 cm (2 in), with a minimal
petiole of 2-3mm; the upper surface is rough.[10] The
perfect, wind-pollinated
apetalous flowers are produced on second-year shoots in March,[11] followed by obovate
samarae < 19 mm (3/4 in) long × < 14 mm (1/2 in) wide.[12]
The tree was briefly propagated and marketed by the Hillier & Sons nursery,
Winchester, Hampshire from 1971 to 1977, during which time only four were sold.[14][15]
There are no known
cultivars of this taxon, nor is it known to be in commerce beyond the United States.
American testing
The David Elm has shown some promise as a result of testing at the
Ohio State University (OSU) in
Ohio.[16][17] At OSU, the plants were cultivated in copper-lined pots and planted in a wide lawn under a powerline and in small home lawns. The tree's performance has been mixed, but shows potential. Some specimens did extremely well, while others struggled. The tree seems to perform well on disturbed sites, in calciferous (alkaline) soils, and also seems to have a better tolerance for wet soil than the literature has indicated. A number of strong saplings were cultivated that show promise. Some saplings underwent judicious pruning early on to maximize structural stability of the plant ("pruning can help the plant result in a more structurally stable branching pattern" [16]), and blue-colored tree shelters were used on some plants until the stem reached a diameter of 25–37 mm.
Additional observation shows that at least 50% of emerging leaves on the trees survived a hard freeze that lasted 5 days during April 2007. Leaves were approximately 70% emerged when temperatures fell to −6°
C (21°
F). Temperatures fell below freezing for 5 days (April 4–8, 2007).
Notable trees
The UK
TROBI Champion is a relatively young tree at White House Farm,
Ivy Hatch, Kent, measuring 5 m high by 17 cm
d.b.h. in 2009.[18]
Etymology
The tree is named for Father
Armand David, the French missionary and naturalist who introduced the tree to France in the 19th century.
Accessions
North America
Arnold Arboretum, US. Acc. nos. 5957 (wild collected), 785-80 (cult. from wild material).
^
abFu, 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]
^Kozhevnikov, Andrey E.; Kozhevnikova Zoya V.; Kwak, Myounghai; Lee, Byoung Yoon (2019), Illustrated Flora of the Primorsky Territory (Russian Far East), National Institute of Biological Resources, Incheon, South Korea
^Hilliers' Manual of Trees & Shrubs. Ed. 3, 399, (1973); David & Charles, Newton Abbot, UK
^Hilliers' Manual of Trees & Shrubs. Ed. 6, 369, 370, (2002); David & Charles, Newton Abbot, UK
^Ware, G. (1995). Little-known elms from China: landscape tree possibilities. Journal of Arboriculture, (Nov. 1995). International Society of Arboriculture, Champaign, Illinois, US.
[2]Archived 2007-11-30 at the
Wayback Machine
Jung, Mee Jung, Seong-Il Heo, and Myeong-Hyeon Wang. Free radical scavenging and total phenolic contents from
methanolic extracts of Ulmus davidiana. Food Chemistry 108.2 (2008): 482-487.