Ulmus gausseniiW. C. Cheng, theAnhui, orhairy, elm, is a medium sizedeciduous tree whose natural range is restricted to the valleys of theLangya limestone mountains ofChu Xian[2] inAnhui Province, easternChina.[3] The tree was most commonly found on the flood plains, indicating a tolerance of periodic inundation. However,U. gaussenii is now possibly the rarest and most endangered elm species, with only approximately 30 trees known to survive in the wild in 2009.[4]
The tree was introduced to the West in 1995, at theMorton Arboretum,Illinois, as part of an evaluation of Chinese elms for landscape use.[5] However, closer examination of the leaves at the Morton suggests that their trees are in factUlmus castaneifolia.[6]
The tree can grow to a height of about 25 m, with a slender trunk < 0.8 md.b.h. The bark is longitudinally fissured and almost black. The leaves are generallyobovate, < 11 cm long, borne on densely pubescent reddish twigs, sometimes featuring flat corky wings. The wind-pollinatedapetalous flowers appear in March, the large orbicularsamarae < 28 mm in diameter ripen in April.[7][8]
The species is cultivated inJiangsu (Nanjing),[8] but remains very rare in cultivation in the West. In artificial freezing tests at the Morton Arboretum theLT50 (temp. at which 50% of tissues die) was found to be -30.7 °C.[10] The Anhui elm was considered of particular interest, as its riparian habitat suggests it tolerates anoxic ground during prolonged flooding.[11] Very few specimens are cultivated (2019) in Europe, notably in the UK and the Netherlands. There are no knowncultivars of this taxon, nor is it known to be in commerce.
^Fu, L. and Xin, Y. 'Elms of China' in Dunn, C. P. (ed.) (2000).The Elms - Breeding, Conservation, and Disease Management., Part 1, Taxonomy, 21-44. Springer Science + Business Media, New York.ISBN978-1-4613-7032-1
^Grimshaw, J. & Bayton, R. (2009).New Trees - Recent Introductions to Cultivation. RBG Kew, London.ISBN978-1-84246-173-0
^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 theWayback Machine
^abBrookes, A. H. (2022).Great Fontley Elm Trial, 2022 Report. Butterfly Conservation,Lulworth, England.
^Fu, L. & Jin J. (eds). (1992).China Red Data Book. Rare and endangered plants. Vol. 1. Science Press, Beijing
^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.[3]
^Shirazi, A. M. & Ware, G. H. (2004).Evaluation of New Elms from China for Cold Hardiness in Northern Latitudes. International Symposium on Asian Plant Diversity & Systematics 2004,Sakura,Japan.
^Dirr, M. (2009). 'Future Tree Selections'.Western, Spring 2009, p.8. Western Nursery & Landscape Association, St Joseph, Missouri.[4]
^Cheng, W. C. (1939). 'Ulmus gaussenii'.Travaux du Laboratoire Forestier de Toulouse. 3(3): 110. 1939.
