Ulmus americana 'Lewis & Clark' = Prairie Expedition
| Ulmus americana | |
|---|---|
 Prairie Expedition leaves, midsummer | |
| Cultivar | 'Lewis & Clark' = Prairie Expedition™ |
| Origin | North Dakota State University Research Foundation, USA |
The American Elm cultivar Ulmus americana 'Lewis & Clark' (trade name Prairie Expedition) is a relatively new development from the North Dakota State University (NDSU) Research Foundation breeding programme, released in 2004 to commemorate the 200th anniversary of the eponymous expedition . The cultivar was cloned from a tree discovered in 1994 along the Wild Rice River south west of Fargo, ND., where all those around it had succumbed to Dutch elm disease; the tree remains in perfect health (2008).
Description
Prairie Expedition is distinguished in maturity by its broad umbrella crown and dark green foliage. The clone grows moderately quickly, averaging an increase of > 1 m in height per annum when young, reaching a height of <17 m in 25 to 30 years . The leaves are < 13 cm in length by 9 cm broad, coarsely-toothed, and with a 4 mm petiole.
Pests and diseases
Possession of an innate resistance to Dutch elm disease was suggested after inoculation with the causal fungus at the NDSU,[1] however replication of the tests is considered too limited to be conclusive. No other specific information available, but the species generally is highly susceptible to Elm Yellows; it is also moderately preferred for feeding and reproduction by the adult Elm Leaf Beetle Xanthogaleruca luteola [2] , and highly preferred for feeding by the Japanese Beetle Popillia japonica [3] in the United States.
Cultivation
Prairie Expedition has been included in the National Elm Trial coordinated by Colorado State University. The tree is in commerce in the USA, and was introduced to the UK from Canada in 2008,[4] and to the Netherlands in 2010.
Etymology
The tree is named for the Lewis & Clark prairie expedition of 1804.
Accessions
North America
- North Dakota State University, no details known.
Europe
- Grange Farm Arboretum, Sutton St James, Spalding, Lincolnshire, UK. Acc. no. 1054
- Great Fontley, Fareham, UK, Butterfly Conservation Elm trials plantation, Home Field. One tree planted 2008, d.b.h. = 5 cm in 2015.[5]
Nurseries
North America
- Bylands Nurseries Ltd. , Kelowna, British Columbia, Canada.
- Patmore Nursery , Brandon, Manitoba
- Sun Valley Garden Centre , Eden Prairie, Minnesota
References
- ↑ Capps, T. K. (1996). Selection, propagation and inoculation of American Elms with potential Dutch elm disease resistance. MSc thesis, NDSU.
- ↑ Miller, F. and Ware, G. (2001). Resistance of Temperate Chinese Elms (Ulmus 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 (Ulmus spp.) for the Feeding of the Japanese Beetle (Coleoptera: Scarabaeidae). Journal of Economic Entomology 94 (2). 445–448. 2001. Entom. Soc.of America.
- ↑ Brookes, A. H. (2015). Disease-resistant elms, Butterfly Conservation trials report, 2015 Butterfly Conservation, Hants & IoW Branch, England.
- ↑ Brookes, A. (2015). Great Fontley Elm Trial, 2015 Report. Butterfly Conservation, Lulworth, UK.
External links
- http://ndsuresearchfoundation.org/Prairie%20Expedition-RFM-37.htm U. americana Lewis & Clark Prairie Expedition NDSU Plant Sciences Introduction.
- http://treehealth.agsci.colostate.edu/research/nationalelmtrial/NationalElmTrial.htm National Elm Trial