Ulmus americana 'Delaware'
From Wikipedia, the free encyclopedia
| Ulmus americana |
|---|
| Cultivar |
| 'Delaware' |
| Origin |
| USDA, Morristown, New Jersey, USA |
The American Elm Ulmus americana cultivar 'Delaware' was originally selected (as tree number 218) from 35,000 seedlings inoculated with the Dutch elm disease fungus in USDA trials at Morristown, New Jersey. Further trials were conducted by both the USDA and the United States National Arboretum, which confirmed the clone had a fair level of resistance to the disease. Although propagated for further trials, the tree was never commercially released, as it is known to have a relatively low stature and undesirable branching habit [1] [2]. Like all other American Elm cultivars, 'Delaware' is susceptible to elm yellows but resistant to elm leaf beetle. The original tree, which had been moved to the USDA National Arboretum, Washington, D. C. in 1948, died from unknown causes (probably elm yellows, by some accounts) in 1980, but a clone survives at the Denver Botanic Gardens, as 'Delaware II'.
The tree is not known to have been introduced to Europe or Australasia.
NB 'Delaware I' is the original name given to the hybrid 'Urban' before its commercial release.
Contents |
[edit] Arboreta etc. accessions
[edit] North America
- Brooklyn Botanic Garden [1], New York, acc. no. 980489.
- Dawes Arboretum [2], Newark, Ohio. 1 trees, listed as 'Delaware #2', no acc. details available.
- Denver Botanic Gardens, no details available.
- Dominion Arboretum, Canada, [3] No details available.
[edit] Nurseries
[edit] North America
[edit] Synonymy
- 'Delaware II'.
[edit] References
- ^ Santamour, F. S., & Bentz, S. E. Updated checklist of elm (Ulmus) cultivars for use in North America. Journal of Arboriculture, 21(3): May, 1995.
- ^ Townsend, A. M., Bentz, S. E., and Douglass L. W. (2005). Evaluation of 19 American Elm Clones for Tolerance to Dutch Elm Disease. Journal of Environmental Horticulture, March 2005, Horticultural Research Institute, Washington, D.C.
