Ulmus americana 'Pendula'
The American Elm cultivar Ulmus americana 'Pendula' is considered probably just a forma by Green, although it was originally listed by William Aiton in Hort. Kew, 1: 320, 1789 as U. americana var. pendula, cloned in England in 1752 by James Gordon.
NB: 'Pendula' was later confused with a pendulous variant of U. glabra.
The tree was described as vase-shaped with branches pendulous at their extremities.
Pests and diseases
The clone's resistance to Dutch Elm Disease is not known, but the species is highly susceptible to the disease and Elm Yellows; it is also moderately preferred for feeding and reproduction by the adult Elm Leaf Beetle Xanthogaleruca luteola  , and highly preferred for feeding by the Japanese Beetle Popillia japonica    in the United States. U. americana is also the most susceptible of all the elms to verticillium wilt.
'Pendula' is only known to have been cultivated in the UK and the Netherlands; no surviving (2016) trees have been confirmed.
- Ulmus americana var. glabra: Walpers, Ann. Bot. Syst. 3: 424, 1852.
- Green, Peter Shaw (1964). "Registration of cultivar names in Ulmus". Arnoldia. Arnold Arboretum, Harvard University. 24 (6–8): 41–80. Retrieved 16 February 2017.
- Aiton, William (1789). "Ulmus". Hortus Kewensis. 1: 320.
- Miller, F. and Ware, G. (2001). Resistance of Temperate Chinese Elms (Ulmuss spp.) to Feeding of the Adult Elm Leaf Beetle (Coleoptera: Chrysomelidae). Journal of Economic Entomology 94 (1): 162–166. 2001. Entom. Soc.of America.
- Miller, F., Ware, G. and Jackson, J. (2001). Preference of Temperate Chinese Elms (Ulmuss spp.) for the Feeding of the Japanese Beetle (Coleoptera: Scarabaeidae). Journal of Economic Entomology 94 (2). 445–448. 2001. Entom. Soc.of America.
- Pegg, G. F. & Brady, B. L. (2002). Verticillium Wilts. CABI Publishing. ISBN 0-85199-529-2
- Went, J. C. (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.